1 00:00:06,173 --> 00:00:07,965 A mysterious tunnel is revealed 2 00:00:07,966 --> 00:00:10,760 below the streets of Washington, D.C. 3 00:00:10,761 --> 00:00:12,428 The corridor ran about 60 feet 4 00:00:12,429 --> 00:00:14,388 before ending in a concrete wall. 5 00:00:14,389 --> 00:00:18,559 Rusted hinges were the only trace of a wooden door 6 00:00:18,560 --> 00:00:21,729 that once led to something beyond. 7 00:00:21,730 --> 00:00:24,482 Someone had built a multilevel labyrinth 8 00:00:24,483 --> 00:00:25,691 beneath the ground. 9 00:00:25,692 --> 00:00:27,944 The only question was why? 10 00:00:27,945 --> 00:00:30,321 Archaeologists make a startling discovery 11 00:00:30,322 --> 00:00:32,198 beneath an Italian town. 12 00:00:32,199 --> 00:00:34,283 An excavation unearthed the facade 13 00:00:34,284 --> 00:00:36,786 of a monumental chamber tomb. 14 00:00:36,787 --> 00:00:40,456 It turned out to be an ancient sarcophagus. 15 00:00:40,457 --> 00:00:43,167 What they found was stunning. 16 00:00:43,168 --> 00:00:45,294 Near a southwestern Colombian town, 17 00:00:45,295 --> 00:00:48,631 massive subterranean chambers are uncovered. 18 00:00:48,632 --> 00:00:50,633 The entire region is heavily affected 19 00:00:50,634 --> 00:00:52,093 by tectonic activity. 20 00:00:52,094 --> 00:00:54,136 Earthquakes are relatively common. 21 00:00:54,137 --> 00:00:55,888 Could these chambers have been built 22 00:00:55,889 --> 00:00:58,349 as some form of protection or even shelter 23 00:00:58,350 --> 00:01:01,102 from some other threat? 24 00:01:01,103 --> 00:01:04,063 Below the busy streets of the world's cities 25 00:01:04,064 --> 00:01:07,775 exists a hidden realm of wonder. 26 00:01:07,776 --> 00:01:11,821 Sprawling ancient complexes, 27 00:01:11,822 --> 00:01:14,532 mysterious tombs, 28 00:01:14,533 --> 00:01:17,535 top-secret military bases, 29 00:01:17,536 --> 00:01:20,162 strange structures, 30 00:01:20,163 --> 00:01:22,665 and lost artifacts 31 00:01:22,666 --> 00:01:26,252 buried beneath our feet and long forgotten 32 00:01:26,253 --> 00:01:28,504 until now. 33 00:01:28,505 --> 00:01:33,342 Underground marvels are exposed to reveal what lies 34 00:01:33,343 --> 00:01:35,804 Hidden Beneath the Cities. 35 00:01:47,816 --> 00:01:50,067 Set between Maryland and Virginia, 36 00:01:50,068 --> 00:01:52,820 Washington, D.C. was defined from the start 37 00:01:52,821 --> 00:01:57,158 by a push and pull between federal authority, local life, 38 00:01:57,159 --> 00:02:01,454 and shifting visions of what the capital should be. 39 00:02:01,455 --> 00:02:03,873 In 1790, George Washington chose the site 40 00:02:03,874 --> 00:02:07,752 {\an8}for a new federal district on the Potomac and Anacostia Rivers 41 00:02:07,753 --> 00:02:10,588 {\an8}on land ceded by Maryland and Virginia. 42 00:02:10,589 --> 00:02:15,176 He appointed Pierre L'Enfant to design a bold modern city 43 00:02:15,177 --> 00:02:18,262 with grand boulevards, ceremonial spaces, 44 00:02:18,263 --> 00:02:19,472 and a central capitol. 45 00:02:19,473 --> 00:02:24,644 It was all inspired by L'Enfant's native city, Paris. 46 00:02:24,645 --> 00:02:25,936 During the Civil War, 47 00:02:25,937 --> 00:02:30,066 Washington's population swelled from 75,000 to 200,000, 48 00:02:30,067 --> 00:02:32,068 {\an8}triggering sanitation crises 49 00:02:32,069 --> 00:02:33,819 {\an8}and a wave of smallpox outbreaks. 50 00:02:33,820 --> 00:02:35,071 In the decades that followed, 51 00:02:35,072 --> 00:02:37,531 new streets, sewer lines, and public parks 52 00:02:37,532 --> 00:02:39,116 began to reshape the city. 53 00:02:39,117 --> 00:02:40,993 {\an8}Around the turn of the century 54 00:02:40,994 --> 00:02:42,870 {\an8}talk of a new Washington 55 00:02:42,871 --> 00:02:45,706 {\an8}reflected the city's rapid transformation. 56 00:02:45,707 --> 00:02:47,625 Gilded Age wealth brought mansions 57 00:02:47,626 --> 00:02:49,168 to the upland neighborhoods, 58 00:02:49,169 --> 00:02:52,421 embassies and statues lent a cosmopolitan air, 59 00:02:52,422 --> 00:02:57,093 and in 1907 work began on the National Cathedral. 60 00:02:57,094 --> 00:03:00,596 Washington was becoming a place everyone wanted to be, 61 00:03:00,597 --> 00:03:02,306 from lobbyists and trade groups 62 00:03:02,307 --> 00:03:06,435 to anyone hoping to shape the nation's future. 63 00:03:06,436 --> 00:03:08,813 In September of 1924, 64 00:03:08,814 --> 00:03:11,232 a truck delivering construction supplies 65 00:03:11,233 --> 00:03:14,985 sinks into an alley behind a house in the city. 66 00:03:14,986 --> 00:03:16,445 When it's pulled free, 67 00:03:16,446 --> 00:03:20,449 it reveals an opening wide enough to climb inside. 68 00:03:20,450 --> 00:03:23,369 {\an8} This clearly wasn't a sinkhole. 69 00:03:23,370 --> 00:03:25,454 {\an8}A nearby resident grabbed a flashlight, 70 00:03:25,455 --> 00:03:29,208 and along with a janitor, went to take a look. 71 00:03:29,209 --> 00:03:32,795 They climbed down into the tunnel about four feet wide, 72 00:03:32,796 --> 00:03:35,965 its walls lined with white-enameled brick 73 00:03:35,966 --> 00:03:38,300 with an arched ornamental ceiling 74 00:03:38,301 --> 00:03:41,804 rising nearly eight feet overhead. 75 00:03:41,805 --> 00:03:43,305 The corridor ran about 60 feet 76 00:03:43,306 --> 00:03:46,142 before ending at a concrete wall. 77 00:03:46,143 --> 00:03:49,979 Rusted hinges on the surface of that wall were the only trace 78 00:03:49,980 --> 00:03:55,526 of a wooden door that once led to something beyond. 79 00:03:55,527 --> 00:03:56,986 But it didn't end there. 80 00:03:56,987 --> 00:04:00,239 A separate passage led down six brick steps to a second tunnel, 81 00:04:00,240 --> 00:04:02,199 which had a trapdoor in the floor. 82 00:04:02,200 --> 00:04:06,370 Beneath it, an iron ladder vanished deeper underground. 83 00:04:06,371 --> 00:04:08,747 Above ground, onlookers gathered 84 00:04:08,748 --> 00:04:10,291 as fresh cracks appeared, 85 00:04:10,292 --> 00:04:13,169 exposing new entrances to the hidden network. 86 00:04:13,170 --> 00:04:16,380 No one could explain it, and rumors spread fast. 87 00:04:16,381 --> 00:04:17,631 Brick by brick, 88 00:04:17,632 --> 00:04:22,386 someone had built a multilevel labyrinth beneath the ground. 89 00:04:22,387 --> 00:04:25,264 The only question was why? 90 00:04:25,265 --> 00:04:27,349 As exploration continues, 91 00:04:27,350 --> 00:04:29,393 one detail stands out. 92 00:04:29,394 --> 00:04:30,436 Inside the tunnel, 93 00:04:30,437 --> 00:04:34,732 clues from a different era begin to surface. 94 00:04:34,733 --> 00:04:38,694 Pasted to the tunnel's ceiling were German newspapers 95 00:04:38,695 --> 00:04:42,698 from 1917 and 1918. 96 00:04:42,699 --> 00:04:45,034 According to early newspaper reports, 97 00:04:45,035 --> 00:04:48,621 many referenced stories about submarine activity 98 00:04:48,622 --> 00:04:53,000 and had cryptic markings that looked like ciphers. 99 00:04:53,001 --> 00:04:57,046 Were these remnants of a covert German intelligence network 100 00:04:57,047 --> 00:05:00,883 operating beneath Washington? 101 00:05:00,884 --> 00:05:03,844 It made sense for people to be worried 102 00:05:03,845 --> 00:05:05,346 about German espionage. 103 00:05:05,347 --> 00:05:08,224 Back in World War I, the Secret Service had seized 104 00:05:08,225 --> 00:05:10,476 the briefcase of Dr. Heinrich Albert. 105 00:05:10,477 --> 00:05:14,021 He was Germany's chief financial agent in America, 106 00:05:14,022 --> 00:05:18,692 and he controlled over $27 million for sabotage, 107 00:05:18,693 --> 00:05:21,403 from strikes and factory disruptions, 108 00:05:21,404 --> 00:05:26,492 to poison gas, even plans for a naval landing near New York. 109 00:05:26,493 --> 00:05:28,202 Some neighbors recalled a German chemist 110 00:05:28,203 --> 00:05:30,371 who once lived nearby and speculated the tunnel 111 00:05:30,372 --> 00:05:33,624 had been used by spies to reach his home during the war. 112 00:05:33,625 --> 00:05:36,919 Neighborhood children said the passengers ran to Rock Creek 113 00:05:36,920 --> 00:05:38,712 and even dropped into the sewers; 114 00:05:38,713 --> 00:05:41,423 a possible escape route for those who knew the way. 115 00:05:41,424 --> 00:05:43,425 As investigators pushed deeper, 116 00:05:43,426 --> 00:05:46,262 parts of the story seem to line up. 117 00:05:46,263 --> 00:05:49,265 One tunnel did track toward Rock Creek. 118 00:05:49,266 --> 00:05:52,309 Others branched off in unexpected directions. 119 00:05:52,310 --> 00:05:55,104 One skirted the home of Washington Post owner 120 00:05:55,105 --> 00:05:56,856 Edward B. McLean. 121 00:05:56,857 --> 00:05:58,941 Another ended in a walled garden, 122 00:05:58,942 --> 00:06:01,610 and a third was blocked with a cement door. 123 00:06:01,611 --> 00:06:05,781 All of this was less than two miles from the National Mall, 124 00:06:05,782 --> 00:06:07,616 close enough to raise genuine alarm 125 00:06:07,617 --> 00:06:11,203 about spies operating underneath Washington. 126 00:06:11,204 --> 00:06:14,123 Over 4,000 miles away in Berlin, 127 00:06:14,124 --> 00:06:17,126 another tunnel reveals how intelligence operations 128 00:06:17,127 --> 00:06:20,379 can unfold entirely out of public view. 129 00:06:20,380 --> 00:06:22,464 Known as Operation Gold, 130 00:06:22,465 --> 00:06:27,553 the Berlin Tunnel was built between 1954 and 1955 131 00:06:27,554 --> 00:06:30,472 by the CIA and Britain's MI6 132 00:06:30,473 --> 00:06:33,142 to tap Soviet military phone lines 133 00:06:33,143 --> 00:06:37,646 carrying traffic between Moscow, Warsaw and Bucharest. 134 00:06:37,647 --> 00:06:43,402 Lined with 125 tons of steel, it ran nearly 1,500 feet deep 135 00:06:43,403 --> 00:06:47,281 across the border into East Berlin. 136 00:06:47,282 --> 00:06:48,616 The tunnel's entrance was hidden 137 00:06:48,617 --> 00:06:52,703 under a U.S. Air Force warehouse in West Berlin. 138 00:06:52,704 --> 00:06:55,998 When it was complete, British technicians installed the taps, 139 00:06:55,999 --> 00:06:57,333 and over the next 11 months, 140 00:06:57,334 --> 00:07:00,502 intercepted hundreds of thousands of calls 141 00:07:00,503 --> 00:07:04,256 and millions of hours of teletype traffic. 142 00:07:04,257 --> 00:07:06,842 Much of it was genuine intelligence, 143 00:07:06,843 --> 00:07:08,761 despite the fact that the Soviets knew 144 00:07:08,762 --> 00:07:11,347 about the tunnel from the start. 145 00:07:11,348 --> 00:07:13,182 In Washington, early reports mentioned 146 00:07:13,183 --> 00:07:15,517 electrical wiring in the tunnel walls, 147 00:07:15,518 --> 00:07:17,561 but its size and construction were nothing like 148 00:07:17,562 --> 00:07:20,439 the purpose-built espionage tunnels in Berlin. 149 00:07:20,440 --> 00:07:23,525 And unlike Operation Gold, no records or credible accounts 150 00:07:23,526 --> 00:07:25,819 ever linked it to intelligence work, 151 00:07:25,820 --> 00:07:26,862 meaning it might have been concealed 152 00:07:26,863 --> 00:07:28,697 for entirely different reasons. 153 00:07:28,698 --> 00:07:31,367 As the discovery dominates the headlines, 154 00:07:31,368 --> 00:07:32,534 some wonder if the tunnels 155 00:07:32,535 --> 00:07:36,121 serve a different kind of clandestine network. 156 00:07:36,122 --> 00:07:38,040 Early newspaper reports claim that 157 00:07:38,041 --> 00:07:40,876 an abundance of bottles was found in the tunnel. 158 00:07:40,877 --> 00:07:42,586 What you have to understand about that 159 00:07:42,587 --> 00:07:46,298 is that Washington enacted Prohibition in 1917, 160 00:07:46,299 --> 00:07:49,385 three years before Prohibition at the national level. 161 00:07:49,386 --> 00:07:53,639 So after that, the city's 267 licensed saloons 162 00:07:53,640 --> 00:07:57,768 multiplied into nearly 3,000 speakeasies. 163 00:07:57,769 --> 00:08:01,563 Hidden beneath candy shops and tucked into drugstore basements, 164 00:08:01,564 --> 00:08:04,358 they kept the capital supplied with alcohol. 165 00:08:04,359 --> 00:08:05,943 Could the tunnel have been part 166 00:08:05,944 --> 00:08:09,279 of the city's illicit trade in liquor? 167 00:08:09,280 --> 00:08:11,115 Bootlegging in Washington 168 00:08:11,116 --> 00:08:13,242 wasn't always discreet. 169 00:08:13,243 --> 00:08:17,246 In one case, a Prohibition Bureau agent found two men 170 00:08:17,247 --> 00:08:20,499 unloading liquor off Pennsylvania Avenue. 171 00:08:20,500 --> 00:08:23,293 Shots were fired, and a stray round 172 00:08:23,294 --> 00:08:26,380 struck Senator Frank Greene of Vermont, 173 00:08:26,381 --> 00:08:29,299 an injury he never recovered from. 174 00:08:29,300 --> 00:08:32,636 In a city where the trade was sometimes public, 175 00:08:32,637 --> 00:08:34,888 a tunnel would have offered bootleggers 176 00:08:34,889 --> 00:08:38,600 the benefit of cover and control. 177 00:08:38,601 --> 00:08:41,311 From 1920 to 1930, George Cassiday, 178 00:08:41,312 --> 00:08:44,690 or "the man in the green hat" as he was known, 179 00:08:44,691 --> 00:08:47,317 was the primary bootlegger for members of Congress. 180 00:08:47,318 --> 00:08:50,821 He kept a basement office in the Cannon House Office Building, 181 00:08:50,822 --> 00:08:52,781 and later moved to the Senate 182 00:08:52,782 --> 00:08:57,327 and made up to 25 deliveries a day with near total freedom. 183 00:08:57,328 --> 00:09:00,330 Despite arrests in 1925 and 1930, 184 00:09:00,331 --> 00:09:02,082 he never named his clients, 185 00:09:02,083 --> 00:09:04,126 but claimed at least 80% of lawmakers 186 00:09:04,127 --> 00:09:05,753 drank during Prohibition. 187 00:09:05,754 --> 00:09:08,172 With demand that high inside the Capitol, 188 00:09:08,173 --> 00:09:10,632 a discrete route would have obvious value. 189 00:09:10,633 --> 00:09:13,343 Over 600 miles northwest of Washington, 190 00:09:13,344 --> 00:09:15,471 Milwaukee's residents found similar methods 191 00:09:15,472 --> 00:09:18,640 to bypass Prohibition restrictions. 192 00:09:18,641 --> 00:09:22,644 In 2021, renovations at the historic Turner Hall 193 00:09:22,645 --> 00:09:26,065 uncovered a cutout in the wall, leading to a hidden room. 194 00:09:26,066 --> 00:09:30,235 Many members of this athletic, cultural, and political society 195 00:09:30,236 --> 00:09:32,571 were part of Milwaukee's German community, 196 00:09:32,572 --> 00:09:34,948 which staunchly opposed Prohibition. 197 00:09:34,949 --> 00:09:37,993 Locals say that the space was connected to a network 198 00:09:37,994 --> 00:09:40,662 of tunnels linking neighborhood bars, 199 00:09:40,663 --> 00:09:43,999 some stretching all the way to the Milwaukee River. 200 00:09:44,000 --> 00:09:46,794 During Prohibition, rumrunners from Canada 201 00:09:46,795 --> 00:09:50,923 crossed Lake Michigan to bring liquor into Wisconsin. 202 00:09:50,924 --> 00:09:57,012 By 1928, the FBI had tallied more than 1,100 speakeasies 203 00:09:57,013 --> 00:10:00,265 operating in Milwaukee alone. 204 00:10:00,266 --> 00:10:04,311 At Turner Hall, traces of that era were found, 205 00:10:04,312 --> 00:10:08,065 including handwritten notes, recipes for hooch, 206 00:10:08,066 --> 00:10:11,401 and personal effects from drinking clubs. 207 00:10:11,402 --> 00:10:13,654 Milwaukee's tunnels show how hidden spaces 208 00:10:13,655 --> 00:10:17,366 might have been used to fuel a thriving underground economy. 209 00:10:17,367 --> 00:10:20,202 But in Washington, 210 00:10:20,203 --> 00:10:21,995 there's no sign the Dupont tunnels 211 00:10:21,996 --> 00:10:24,498 were built or used for profit. 212 00:10:24,499 --> 00:10:29,545 And certain details there point to a story that's way stranger 213 00:10:29,546 --> 00:10:32,422 than anything behind a speakeasy door. 214 00:10:32,423 --> 00:10:34,508 Eventually, the trail leads to one man 215 00:10:34,509 --> 00:10:38,388 with a life as elaborate as the tunnels themselves. 216 00:10:40,598 --> 00:10:41,723 When the tunnels were exposed in 1924, 217 00:10:41,724 --> 00:10:44,184 some longtime neighbors weren't surprised. 218 00:10:44,185 --> 00:10:45,769 They'd seen them seven years earlier 219 00:10:45,770 --> 00:10:48,272 when a steam shovel broke through the same property 220 00:10:48,273 --> 00:10:51,567 which was once owned by Harrison Gray Dyar, Jr., 221 00:10:51,568 --> 00:10:54,653 who was one of America's most accomplished entomologists 222 00:10:54,654 --> 00:10:56,738 and one of its strangest scientific figures. 223 00:10:56,739 --> 00:10:59,032 But why would a man devoted to moths and mosquitoes 224 00:10:59,033 --> 00:11:02,578 spend years meticulously digging tunnels beneath his own home? 225 00:11:02,579 --> 00:11:04,663 Born to a wealthy New York family, 226 00:11:04,664 --> 00:11:08,709 Dyar studied chemistry at MIT and biology at Columbia. 227 00:11:08,710 --> 00:11:11,920 In 1897, he moved to Washington to oversee 228 00:11:11,921 --> 00:11:14,339 the Smithsonian's butterfly and moth collection 229 00:11:14,340 --> 00:11:15,757 while living on his inheritance, 230 00:11:15,758 --> 00:11:19,595 along with his wife Zella and their children. 231 00:11:19,596 --> 00:11:22,848 In 1900, their marriage became strained. 232 00:11:22,849 --> 00:11:24,933 Zella was struggling with hearing loss, 233 00:11:24,934 --> 00:11:28,770 and she didn't want to have any more children, whereas Dyar did. 234 00:11:28,771 --> 00:11:31,356 That same year, Dyar began an affair 235 00:11:31,357 --> 00:11:35,444 with a kindergarten teacher named Wellesca Pollock. 236 00:11:35,445 --> 00:11:38,614 A few years later, Wellesca married another man. 237 00:11:38,615 --> 00:11:41,283 And around that time, Zella asked Dyar 238 00:11:41,284 --> 00:11:44,703 for a hollyhock garden at their home. 239 00:11:44,704 --> 00:11:45,787 He began digging, 240 00:11:45,788 --> 00:11:50,918 and didn't stop until he left the property in 1914. 241 00:11:50,919 --> 00:11:55,631 But it wouldn't be his last time underground. 242 00:11:55,632 --> 00:11:59,009 By 1915, the marriage of the Dyars was collapsing. 243 00:11:59,010 --> 00:12:00,969 He sued Zella for desertion. 244 00:12:00,970 --> 00:12:03,430 She sued him for adultery. 245 00:12:03,431 --> 00:12:07,226 Then, Wellesca tried to divorce her long-absent husband. 246 00:12:07,227 --> 00:12:08,727 This was a man no one had ever seen 247 00:12:08,728 --> 00:12:12,814 and whom many believed was actually Dyar. 248 00:12:12,815 --> 00:12:14,816 Rumors that he'd fathered her three sons 249 00:12:14,817 --> 00:12:16,652 turned out to be true. 250 00:12:16,653 --> 00:12:20,155 And in 1917, that scandal cost Dyar his job 251 00:12:20,156 --> 00:12:21,740 at the Department of Agriculture. 252 00:12:21,741 --> 00:12:24,618 Four years later, he married Wellesca, 253 00:12:24,619 --> 00:12:27,996 and the digging began again. 254 00:12:27,997 --> 00:12:29,998 Beneath the side yard of their new home, 255 00:12:29,999 --> 00:12:32,459 Dyar built an impressive bunker. 256 00:12:32,460 --> 00:12:35,212 The tunnels and shafts drop 24 feet, 257 00:12:35,213 --> 00:12:37,089 with arched ceilings and electric light 258 00:12:37,090 --> 00:12:38,674 strung through the passageways. 259 00:12:38,675 --> 00:12:41,760 Sculpted human and animal heads stared from the walls, 260 00:12:41,761 --> 00:12:44,346 and over one arch, a Latin inscription read, 261 00:12:44,347 --> 00:12:47,015 "The way down to Hell is easy." 262 00:12:47,016 --> 00:12:50,519 Dyar's tunnels were definitely strange undertakings, 263 00:12:50,520 --> 00:12:52,980 but they weren't commercial and they weren't criminal. 264 00:12:52,981 --> 00:12:56,149 These were private environments seemingly shaped for control, 265 00:12:56,150 --> 00:12:57,859 comfort, and personal meaning; 266 00:12:57,860 --> 00:12:59,987 though Dyar insisted that his digging 267 00:12:59,988 --> 00:13:03,615 was nothing more than exercise. 268 00:13:03,616 --> 00:13:07,452 Dyar died of a stroke in 1929. 269 00:13:07,453 --> 00:13:10,872 His tunnels were later used for mushroom cultivation 270 00:13:10,873 --> 00:13:14,626 and considered as World War II air raid shelters, 271 00:13:14,627 --> 00:13:16,211 before being demolished 272 00:13:16,212 --> 00:13:19,756 for the Federal Aviation Administration's headquarters. 273 00:13:19,757 --> 00:13:23,510 The tunnels were partially uncovered in 1958, 274 00:13:23,511 --> 00:13:25,471 but then sealed. 275 00:13:27,724 --> 00:13:29,850 In the science world, Dyar is a bit of a big deal. 276 00:13:29,851 --> 00:13:33,228 He named or co-named almost 3,000 species 277 00:13:33,229 --> 00:13:34,396 of moths and butterflies, 278 00:13:34,397 --> 00:13:37,566 along with 600 different kinds of mosquitoes. 279 00:13:37,567 --> 00:13:39,901 And he's been honored by having a whole bunch 280 00:13:39,902 --> 00:13:42,738 of different insects named after him, almost 70 of them. 281 00:13:42,739 --> 00:13:44,990 But in Washington, he's remembered differently. 282 00:13:44,991 --> 00:13:49,745 He's the human mole, this brilliant, defiant scientist 283 00:13:49,746 --> 00:13:54,666 living a double life above and below ground. 284 00:13:54,667 --> 00:13:57,836 The bizarre tale of Harrison Dyar and his tunnels 285 00:13:57,837 --> 00:14:00,922 reminds us that in some subterranean spaces, 286 00:14:00,923 --> 00:14:04,926 the mystery runs deeper than the complexes themselves. 287 00:14:04,927 --> 00:14:07,888 And his story leaves a broader question. 288 00:14:07,889 --> 00:14:10,682 How many other hidden worlds might still lie 289 00:14:10,683 --> 00:14:14,604 beneath Washington waiting to be uncovered? 290 00:14:26,866 --> 00:14:30,118 Just over 100 miles from Rome, in the northwestern part 291 00:14:30,119 --> 00:14:34,623 of Italy's Campania region is the city of Giugliano. 292 00:14:34,624 --> 00:14:36,041 Giugliano is situated 293 00:14:36,042 --> 00:14:37,709 on a fertile coastal plain 294 00:14:37,710 --> 00:14:41,213 with a population of over 120,000 people. 295 00:14:41,214 --> 00:14:43,799 {\an8}It's part of a string of agricultural communities 296 00:14:43,800 --> 00:14:45,717 {\an8}in Campania that have been active 297 00:14:45,718 --> 00:14:48,470 {\an8}for centuries in this area. 298 00:14:48,471 --> 00:14:50,639 The city is also part of a region 299 00:14:50,640 --> 00:14:52,933 called the Campania Volcanic Arc, 300 00:14:52,934 --> 00:14:55,852 because there's a lot of geological activity here. 301 00:14:55,853 --> 00:14:58,563 {\an8}Earthquakes regularly rock the region, 302 00:14:58,564 --> 00:15:02,234 {\an8}and residents sometimes experience daily tremors. 303 00:15:02,235 --> 00:15:06,655 In 2025, Giugliano and its surrounding area were hit 304 00:15:06,656 --> 00:15:10,659 by their largest earthquake in 40 years. 305 00:15:10,660 --> 00:15:13,328 It's only a short drive to Pompeii, 306 00:15:13,329 --> 00:15:15,497 the town famous for being buried 307 00:15:15,498 --> 00:15:17,791 by a devastating volcanic eruption 308 00:15:17,792 --> 00:15:20,794 from nearby Mount Vesuvius. 309 00:15:20,795 --> 00:15:23,839 {\an8}Giugliano is also an area designated 310 00:15:23,840 --> 00:15:28,176 {\an8}for potential evacuation in case of another devastating blast 311 00:15:28,177 --> 00:15:30,178 from this dreaded volcano. 312 00:15:30,179 --> 00:15:31,471 Just outside of town, 313 00:15:31,472 --> 00:15:33,598 in a cluster of volcanic craters 314 00:15:33,599 --> 00:15:35,600 known as the Phlegraean Fields, 315 00:15:35,601 --> 00:15:37,936 an archaeological survey is being conducted 316 00:15:37,937 --> 00:15:41,690 in advance of a planned update to Giugliano's water system. 317 00:15:41,691 --> 00:15:44,693 And the results are incredible. 318 00:15:44,694 --> 00:15:46,570 {\an8} An excavation unearthed the facade 319 00:15:46,571 --> 00:15:48,989 {\an8}of a monumental chamber tomb 320 00:15:48,990 --> 00:15:53,034 with a large piece of volcanic rock covering its entrance. 321 00:15:53,035 --> 00:15:56,329 Inside, the tomb was a revelation. 322 00:15:56,330 --> 00:15:57,998 The funerary chamber itself 323 00:15:57,999 --> 00:16:00,667 was approximately 10 feet underground 324 00:16:00,668 --> 00:16:03,420 and measured around 10 by 13 feet. 325 00:16:03,421 --> 00:16:06,965 The tightly sealed entryway had helped keep the burial site 326 00:16:06,966 --> 00:16:10,719 in a remarkable state of preservation. 327 00:16:10,720 --> 00:16:13,054 Two coffins were laid on funeral beds, 328 00:16:13,055 --> 00:16:16,433 and towering over them were a number of frescoes, 329 00:16:16,434 --> 00:16:18,852 including paintings which depicted monsters 330 00:16:18,853 --> 00:16:21,813 from classical mythology. 331 00:16:21,814 --> 00:16:24,733 One fresco showed the Greco-Roman god Hercules 332 00:16:24,734 --> 00:16:26,234 and fellow deity, Mercury, 333 00:16:26,235 --> 00:16:29,738 facing off against the three-headed dog Cerberus, 334 00:16:29,739 --> 00:16:32,657 considered to be the guardian of the underworld. 335 00:16:32,658 --> 00:16:36,244 The other featured two creatures called ichthyocentaurs. 336 00:16:36,245 --> 00:16:40,373 Half men, half horses with green, coiled fish tails, 337 00:16:40,374 --> 00:16:44,252 who were accompanied by two winged, Cupid-like babies. 338 00:16:44,253 --> 00:16:47,797 The colors of both paintings remained incredibly vibrant. 339 00:16:47,798 --> 00:16:49,424 And there were other discoveries, 340 00:16:49,425 --> 00:16:52,260 including three altars called klinai 341 00:16:52,261 --> 00:16:53,595 that held ceramic vessels 342 00:16:53,596 --> 00:16:55,889 which would have been used for libations. 343 00:16:55,890 --> 00:16:58,308 There was also evidence of cremated remains 344 00:16:58,309 --> 00:17:00,185 beside the coffins. 345 00:17:00,186 --> 00:17:03,146 To say this was an important archaeological find 346 00:17:03,147 --> 00:17:04,648 is an understatement. 347 00:17:04,649 --> 00:17:07,609 The question is who was buried here? 348 00:17:07,610 --> 00:17:08,777 Archaeologists noticed 349 00:17:08,778 --> 00:17:11,154 another mysterious object in the tomb. 350 00:17:11,155 --> 00:17:13,698 It appears to be a table of some kind. 351 00:17:13,699 --> 00:17:17,036 But they soon discover it is much more than that. 352 00:17:19,247 --> 00:17:21,373 It turned out to be an ancient sarcophagus. 353 00:17:21,374 --> 00:17:22,666 Before it was opened, 354 00:17:22,667 --> 00:17:25,210 a miniature camera was threaded inside 355 00:17:25,211 --> 00:17:30,340 so that the contents could be seen without being disturbed. 356 00:17:30,341 --> 00:17:33,051 What they found was stunning: 357 00:17:33,052 --> 00:17:36,972 an exceptionally well-preserved human skeleton 358 00:17:36,973 --> 00:17:41,768 laying on its back, covered by a shroud. 359 00:17:41,769 --> 00:17:44,104 Beside the remains were grave goods, 360 00:17:44,105 --> 00:17:47,649 like glass jars for ointment and perfume, 361 00:17:47,650 --> 00:17:50,360 as well as an instrument called a strigil, 362 00:17:50,361 --> 00:17:56,324 which ancient Greeks and Romans used to scrape their skin clean. 363 00:17:56,325 --> 00:17:59,744 The perfectly sealed tomb created a micro-climate 364 00:17:59,745 --> 00:18:02,914 that allowed for an incredible level of preservation. 365 00:18:02,915 --> 00:18:06,668 Interestingly, the artifacts found inside the sarcophagus 366 00:18:06,669 --> 00:18:09,379 were slightly older than the artifacts found 367 00:18:09,380 --> 00:18:11,339 throughout the rest of the tomb. 368 00:18:11,340 --> 00:18:14,217 This suggests the individual in the sarcophagus 369 00:18:14,218 --> 00:18:18,805 was the first burial here and likely the elder of the family. 370 00:18:18,806 --> 00:18:21,266 The site is dubbed the Tomb of Cerberus, 371 00:18:21,267 --> 00:18:24,102 and an inscription marking its final internment 372 00:18:24,103 --> 00:18:30,025 to the year 27 CE places its age at roughly 2,000 years old. 373 00:18:30,026 --> 00:18:33,528 The tomb is not far from the Roman colony of Liternum, 374 00:18:33,529 --> 00:18:36,448 where over 300 veteran soldiers retired 375 00:18:36,449 --> 00:18:38,450 during the 2nd century BCE. 376 00:18:38,451 --> 00:18:41,703 The Roman Empire was often plagued by epidemics, 377 00:18:41,704 --> 00:18:43,872 and traveling soldiers in particular 378 00:18:43,873 --> 00:18:47,876 could easily contract and spread virulent diseases. 379 00:18:47,877 --> 00:18:52,005 The infamous Antonine Plague that exploded in 165 CE, 380 00:18:52,006 --> 00:18:55,925 was reportedly killing 2,000 people a day at its height. 381 00:18:55,926 --> 00:18:58,261 So maybe the body in the sarcophagus 382 00:18:58,262 --> 00:19:00,889 belongs to a high ranking Roman soldier 383 00:19:00,890 --> 00:19:04,434 who contracted some kind of sickness while away fighting 384 00:19:04,435 --> 00:19:06,895 and then was buried here. 385 00:19:06,896 --> 00:19:08,897 The elder skeleton was analyzed, 386 00:19:08,898 --> 00:19:12,567 and herbs found on the body were determined to be wormwood 387 00:19:12,568 --> 00:19:14,361 and something called goosefoot, 388 00:19:14,362 --> 00:19:17,906 both of which have purifying and antiseptic qualities. 389 00:19:17,907 --> 00:19:20,283 These ointments are believed to have been used 390 00:19:20,284 --> 00:19:21,451 to preserve the body. 391 00:19:21,452 --> 00:19:24,579 But could they also have been employed to treat disease? 392 00:19:24,580 --> 00:19:27,415 And could the rock that sealed the entrance to the tomb 393 00:19:27,416 --> 00:19:31,753 had been put in place out of fear that the contagions inside 394 00:19:31,754 --> 00:19:33,880 might escape the burial site? 395 00:19:33,881 --> 00:19:36,132 It's certainly possible that the individual 396 00:19:36,133 --> 00:19:41,346 in the sarcophagus was a soldier who succumbed to an epidemic. 397 00:19:41,347 --> 00:19:44,265 But the thing is, the Romans would sometimes resort 398 00:19:44,266 --> 00:19:48,269 to placing the dead from a plague into mass graves 399 00:19:48,270 --> 00:19:53,274 or hurried burials as the most efficient form of internment, 400 00:19:53,275 --> 00:19:57,612 and given the meticulous burial in the Tomb of Cerberus, 401 00:19:57,613 --> 00:20:00,699 this scenario seems improbable. 402 00:20:00,700 --> 00:20:02,117 It's still a possibility 403 00:20:02,118 --> 00:20:04,160 that they were a high ranking soldier, 404 00:20:04,161 --> 00:20:06,955 but maybe not one who died from an epidemic. 405 00:20:06,956 --> 00:20:09,040 The imagery found within the tomb 406 00:20:09,041 --> 00:20:13,128 and its location may point to a belief in the occult. 407 00:20:13,129 --> 00:20:16,297 The ancient Greeks called this volcanic landscape 408 00:20:16,298 --> 00:20:20,051 "the fiery fields," and within Greco-Roman traditions, 409 00:20:20,052 --> 00:20:22,470 it was considered to be a physical gateway 410 00:20:22,471 --> 00:20:23,888 to the afterlife. 411 00:20:23,889 --> 00:20:26,057 The choice to place the tomb here 412 00:20:26,058 --> 00:20:27,767 suggests a deep understanding 413 00:20:27,768 --> 00:20:30,770 of the spiritual importance of this location. 414 00:20:30,771 --> 00:20:34,023 The frescoes of Cerberus and the ichthyocentaurs 415 00:20:34,024 --> 00:20:36,151 are also potential signifiers 416 00:20:36,152 --> 00:20:38,611 that the family who controlled this tomb 417 00:20:38,612 --> 00:20:41,823 knew the roles these mythological creatures played 418 00:20:41,824 --> 00:20:43,324 in the afterlife. 419 00:20:43,325 --> 00:20:45,076 While Cerberus was the guardian 420 00:20:45,077 --> 00:20:46,828 of the underworld, Hades, 421 00:20:46,829 --> 00:20:49,998 the ichthyocentaurs had been interpreted to be 422 00:20:49,999 --> 00:20:52,834 spiritual guides who could escort the deceased 423 00:20:52,835 --> 00:20:56,004 to the paradise of the so-called Blessed Isles. 424 00:20:56,005 --> 00:20:57,756 During this era, the Roman Empire 425 00:20:57,757 --> 00:21:00,258 certainly had its share of mysterious cults 426 00:21:00,259 --> 00:21:03,762 that possessed secret theories about the afterlife. 427 00:21:03,763 --> 00:21:05,972 So was the deceased a high ranking member 428 00:21:05,973 --> 00:21:07,891 of one of these groups? 429 00:21:07,892 --> 00:21:10,393 It's highly plausible that these cults, 430 00:21:10,394 --> 00:21:13,938 known as "mysteries," had a presence in this region. 431 00:21:13,939 --> 00:21:15,732 Not far from the burial site 432 00:21:15,733 --> 00:21:19,068 is the necropolis of the town of Cumae. 433 00:21:19,069 --> 00:21:22,071 Deep below the ground is an ornate complex 434 00:21:22,072 --> 00:21:24,991 where, according to legend, an oracle would commune 435 00:21:24,992 --> 00:21:28,369 with the Greco-Roman god Apollo. 436 00:21:28,370 --> 00:21:31,331 Similarly, when the tomb of Cerberus was built, 437 00:21:31,332 --> 00:21:34,334 you can imagine that the intention was to provide 438 00:21:34,335 --> 00:21:38,129 the deceased with direct communion with the gods. 439 00:21:38,130 --> 00:21:40,215 Ultimately, though, there's no evidence 440 00:21:40,216 --> 00:21:43,510 that the individuals in the tomb had any kind of membership 441 00:21:43,511 --> 00:21:46,387 in one of the mystery cults of the day. 442 00:21:46,388 --> 00:21:49,974 Far from being representative of a belief in magic 443 00:21:49,975 --> 00:21:53,186 and the occult, the frescoes in the Cerberus tomb 444 00:21:53,187 --> 00:21:57,524 may simply be indicative of an elite and educated family 445 00:21:57,525 --> 00:21:58,900 that was well versed 446 00:21:58,901 --> 00:22:02,070 in the fashionable cultural signifiers of the day. 447 00:22:02,071 --> 00:22:04,072 The status of the family interred here 448 00:22:04,073 --> 00:22:07,617 may ultimately be the key to understanding the origins 449 00:22:07,618 --> 00:22:10,036 of this enigmatic burial site. 450 00:22:10,037 --> 00:22:12,747 This idea of a highly honored senior member 451 00:22:12,748 --> 00:22:16,292 of a wealthy clan is supported by the incredible care 452 00:22:16,293 --> 00:22:19,671 that was lavished on the body found in the sarcophagus. 453 00:22:19,672 --> 00:22:22,173 It's very possible that they were a wealthy member 454 00:22:22,174 --> 00:22:26,261 of the nearby Liternum settlement. 455 00:22:26,262 --> 00:22:28,263 The shroud, the preservative ointments, 456 00:22:28,264 --> 00:22:30,723 and instruments laid around the remains 457 00:22:30,724 --> 00:22:34,561 are all evidence of the respect this person commanded 458 00:22:34,562 --> 00:22:35,728 within their community. 459 00:22:35,729 --> 00:22:38,940 Ultimately, much about the Tomb of Cerberus 460 00:22:38,941 --> 00:22:40,441 remains unclear. 461 00:22:40,442 --> 00:22:43,278 A thorough scientific analysis of the skeleton 462 00:22:43,279 --> 00:22:47,448 may one day give us a better idea of who this person was. 463 00:22:47,449 --> 00:22:50,827 Until then, it seems the three-headed monster 464 00:22:50,828 --> 00:22:53,329 on the vibrant fresco who stands guard 465 00:22:53,330 --> 00:22:55,123 at the gates of the underworld, 466 00:22:55,124 --> 00:22:58,293 is also protecting the centuries-old secrets 467 00:22:58,294 --> 00:23:01,589 locked inside this mysterious tomb. 468 00:23:14,310 --> 00:23:15,935 Tucked into the remote reaches 469 00:23:15,936 --> 00:23:17,687 of southwestern Colombia, 470 00:23:17,688 --> 00:23:22,108 the Tierradentro National Park spans several square kilometers 471 00:23:22,109 --> 00:23:25,320 along the highest ridges of the Colombian Andes. 472 00:23:25,321 --> 00:23:27,322 {\an8} The park is made up of four distinct areas 473 00:23:27,323 --> 00:23:29,490 {\an8}that stretch along the Andes Range. 474 00:23:29,491 --> 00:23:31,242 The terrain is incredibly variable, 475 00:23:31,243 --> 00:23:35,288 ranging from 4,000 to more than 8,000 feet above sea level. 476 00:23:35,289 --> 00:23:36,915 These steep elevation changes, 477 00:23:36,916 --> 00:23:38,958 coupled with the tropical climate, 478 00:23:38,959 --> 00:23:40,793 create sudden and dramatic shifts in weather 479 00:23:40,794 --> 00:23:45,298 and temperature, often within just a few kilometers. 480 00:23:45,299 --> 00:23:48,301 {\an8} The Andes are marked by two principal rainy seasons: 481 00:23:48,302 --> 00:23:51,220 {\an8}one in the spring and one in the fall. 482 00:23:51,221 --> 00:23:55,058 Together, they bring nearly 60 inches of rainfall every year. 483 00:23:55,059 --> 00:23:56,851 The rain helps sustain the forests 484 00:23:56,852 --> 00:23:58,603 that cover the mountains themselves 485 00:23:58,604 --> 00:24:01,022 and eventually drains down to the valleys below, 486 00:24:01,023 --> 00:24:04,359 enriching the soil with sediment. 487 00:24:04,360 --> 00:24:06,194 {\an8} Tierradentro also happens to be 488 00:24:06,195 --> 00:24:08,613 {\an8}one of the most important archaeological sites 489 00:24:08,614 --> 00:24:11,532 {\an8}in Colombia; but it's incredibly remote. 490 00:24:11,533 --> 00:24:13,701 There are no flights close to the area, 491 00:24:13,702 --> 00:24:17,288 and the nearest city is about a five-hour drive away. 492 00:24:17,289 --> 00:24:20,375 The roads are rough, cell phone service is patchy, 493 00:24:20,376 --> 00:24:22,877 and the area is prone to landslides, 494 00:24:22,878 --> 00:24:26,589 which can make getting to the site nearly impossible. 495 00:24:26,590 --> 00:24:29,550 Nearly impossible, but not totally impossible, 496 00:24:29,551 --> 00:24:33,388 because the site has been the subject of archaeological study. 497 00:24:33,389 --> 00:24:34,764 When archaeologists began 498 00:24:34,765 --> 00:24:38,226 to systematically investigate the Tierradentro Park, 499 00:24:38,227 --> 00:24:40,561 they uncover a remarkable site 500 00:24:40,562 --> 00:24:43,356 concealed beneath the forest canopy. 501 00:24:43,357 --> 00:24:45,024 {\an8} Several meters below the surface, 502 00:24:45,025 --> 00:24:48,152 {\an8}explorers uncovered enormous chambers 503 00:24:48,153 --> 00:24:51,114 carved right into the rock. 504 00:24:51,115 --> 00:24:53,241 These ranged from small structures 505 00:24:53,242 --> 00:24:54,867 with a single small room 506 00:24:54,868 --> 00:24:58,246 to massive 40-foot-wide chambers 507 00:24:58,247 --> 00:25:01,541 with support columns. 508 00:25:01,542 --> 00:25:03,334 These underground chambers are a testament 509 00:25:03,335 --> 00:25:05,461 to the engineering skill of the people who built them, 510 00:25:05,462 --> 00:25:07,588 especially given that they were likely excavated 511 00:25:07,589 --> 00:25:08,798 entirely by hand. 512 00:25:08,799 --> 00:25:11,926 This was largely possible because of the local geology. 513 00:25:11,927 --> 00:25:13,261 The volcanic landscape of the Andes 514 00:25:13,262 --> 00:25:16,139 left behind thick layers of hardened ash, 515 00:25:16,140 --> 00:25:19,142 which formed a relatively soft and workable stone. 516 00:25:19,143 --> 00:25:20,810 Radiocarbon dating tells us 517 00:25:20,811 --> 00:25:23,521 that these underground chambers were likely carved out 518 00:25:23,522 --> 00:25:27,734 {\an8}and used from about 600 to 900 CE, 519 00:25:27,735 --> 00:25:31,237 {\an8}long before the Spanish colonized Colombia. 520 00:25:31,238 --> 00:25:34,532 But what exactly were these structures for? 521 00:25:34,533 --> 00:25:36,784 The underground chambers' unique geography 522 00:25:36,785 --> 00:25:40,538 and architecture point to a possible explanation. 523 00:25:40,539 --> 00:25:43,166 The name Tierradentro was first used 524 00:25:43,167 --> 00:25:45,835 by the Spanish conquistadors back in the 1500s, 525 00:25:45,836 --> 00:25:50,548 and it translates roughly to "the interior land" or "inland," 526 00:25:50,549 --> 00:25:54,844 which fits because this region is way off the beaten path. 527 00:25:54,845 --> 00:25:58,139 It is tucked deep into the mountains and forests, 528 00:25:58,140 --> 00:25:59,640 far from the coast. 529 00:25:59,641 --> 00:26:01,184 Now, why here? 530 00:26:01,185 --> 00:26:04,604 Well, maybe the remoteness was the whole point. 531 00:26:04,605 --> 00:26:06,981 Maybe the ancient people built these underground chambers 532 00:26:06,982 --> 00:26:10,526 way out here and hid them below ground for protection 533 00:26:10,527 --> 00:26:13,821 or an edge against potential invaders. 534 00:26:13,822 --> 00:26:15,615 Looking back, we can see several examples 535 00:26:15,616 --> 00:26:18,201 of incredibly impressive military fortifications 536 00:26:18,202 --> 00:26:19,660 in the Andes Mountains. 537 00:26:19,661 --> 00:26:22,663 One of the most famous examples is Sacsayhuamán, 538 00:26:22,664 --> 00:26:23,748 a massive Inca fortress 539 00:26:23,749 --> 00:26:26,876 that sits above the city of Cusco in Peru. 540 00:26:26,877 --> 00:26:30,755 It was built during the 15th century using huge stone blocks, 541 00:26:30,756 --> 00:26:32,924 some of which reach nearly 30 feet tall 542 00:26:32,925 --> 00:26:34,383 and weigh several tons. 543 00:26:34,384 --> 00:26:37,512 The fortress is so strong that it survived earthquakes 544 00:26:37,513 --> 00:26:40,723 that easily take down more modern buildings in the area. 545 00:26:40,724 --> 00:26:42,975 Because it was so strategically important, 546 00:26:42,976 --> 00:26:46,521 Sacsayhuamán played a huge role in the Incas' last stand 547 00:26:46,522 --> 00:26:49,148 against the Spanish conquistadors. 548 00:26:49,149 --> 00:26:51,192 Some of the most intense and bloody battles 549 00:26:51,193 --> 00:26:52,527 happened right here, 550 00:26:52,528 --> 00:26:56,072 as the Incas tried to hold on to their fortress. 551 00:26:56,073 --> 00:26:59,992 In the end, the Spanish managed to take control of Sacsayhuamán 552 00:26:59,993 --> 00:27:02,203 after months of fierce fighting. 553 00:27:02,204 --> 00:27:04,455 But there's another legendary Andean site 554 00:27:04,456 --> 00:27:06,457 that was so well hidden 555 00:27:06,458 --> 00:27:10,795 the conquistadors never even found it. 556 00:27:10,796 --> 00:27:13,631 Machu Picchu stands about 50 miles northwest 557 00:27:13,632 --> 00:27:17,593 of Cusco, roughly 8,000 feet above sea level. 558 00:27:17,594 --> 00:27:21,180 It's a massive site spread over 80,000 acres 559 00:27:21,181 --> 00:27:23,975 of steep mountain peaks and slopes. 560 00:27:23,976 --> 00:27:26,853 Although it was probably built in the 15th century, 561 00:27:26,854 --> 00:27:30,481 Machu Picchu was essentially unknown to the rest of the world 562 00:27:30,482 --> 00:27:32,859 until a local took a professor who was visiting 563 00:27:32,860 --> 00:27:37,488 from Yale University to see it in the early 1900s. 564 00:27:37,489 --> 00:27:38,906 Machu Picchu is actually made up 565 00:27:38,907 --> 00:27:40,074 of hundreds of structures 566 00:27:40,075 --> 00:27:43,995 including enormous fortifying walls and terraces and ramps 567 00:27:43,996 --> 00:27:46,622 that all blend into the landscape. 568 00:27:46,623 --> 00:27:49,709 It was most likely first built as a royal residence 569 00:27:49,710 --> 00:27:51,752 and a retreat for the Inca elite, 570 00:27:51,753 --> 00:27:54,422 but over the years, it may also have served 571 00:27:54,423 --> 00:27:57,843 a bunch of other religious and spiritual functions. 572 00:27:59,469 --> 00:28:01,053 Looking at the Tierradentro chambers, 573 00:28:01,054 --> 00:28:04,432 it becomes clear that they were also intended for the elite. 574 00:28:04,433 --> 00:28:06,434 Carving out these huge underground spaces 575 00:28:06,435 --> 00:28:09,437 required a significant amount of organization and labor, 576 00:28:09,438 --> 00:28:11,480 and wouldn't have been done for just anyone. 577 00:28:11,481 --> 00:28:13,316 But what was it for? 578 00:28:13,317 --> 00:28:14,567 Was it like Machu Picchu, 579 00:28:14,568 --> 00:28:16,611 a retreat for the ancient upper class? 580 00:28:16,612 --> 00:28:19,530 Or did it serve another, more ritualistic function? 581 00:28:19,531 --> 00:28:21,449 Nearly 1,000 miles away, 582 00:28:21,450 --> 00:28:23,910 concealed deep in the Peruvian highlands, 583 00:28:23,911 --> 00:28:26,662 another set of extraordinary underground chambers 584 00:28:26,663 --> 00:28:29,999 raises intriguing possibilities. 585 00:28:30,000 --> 00:28:33,419 Chavín de Huántar is the largest and most important 586 00:28:33,420 --> 00:28:35,796 ruin left by the Chavín people: 587 00:28:35,797 --> 00:28:38,507 an ancient culture that predates the Inca 588 00:28:38,508 --> 00:28:40,676 by more than 2,000 years. 589 00:28:40,677 --> 00:28:43,971 The site stands more than 10,000 feet above sea level 590 00:28:43,972 --> 00:28:47,141 and features a massive stone temple complex 591 00:28:47,142 --> 00:28:50,770 built out of huge rectangular blocks. 592 00:28:50,771 --> 00:28:52,480 The earliest part of the complex 593 00:28:52,481 --> 00:28:54,023 is known as the Old Temple, 594 00:28:54,024 --> 00:28:58,569 and it was built in a distinct U-shape around 900 BCE. 595 00:28:58,570 --> 00:29:01,864 Several centuries later, around 500 BCE, 596 00:29:01,865 --> 00:29:05,326 the New Temple was added, expanding the existing structure 597 00:29:05,327 --> 00:29:07,995 and adding a massive sunken plaza. 598 00:29:07,996 --> 00:29:09,038 These plazas were central 599 00:29:09,039 --> 00:29:12,291 to ancient Andean spiritual and political power, 600 00:29:12,292 --> 00:29:13,459 and would have been the site 601 00:29:13,460 --> 00:29:17,005 of major religious and ceremonial practices. 602 00:29:18,298 --> 00:29:20,341 The site's most unusual feature 603 00:29:20,342 --> 00:29:22,635 sits beneath the temples themselves, 604 00:29:22,636 --> 00:29:24,595 where there's this network of tunnels 605 00:29:24,596 --> 00:29:27,723 and maze-like galleries underground. 606 00:29:27,724 --> 00:29:30,351 Some of them intersect, some of them stand alone. 607 00:29:30,352 --> 00:29:33,521 But these chambers are in near total darkness, 608 00:29:33,522 --> 00:29:36,941 with small tunnels, maybe for ventilation, 609 00:29:36,942 --> 00:29:39,694 but no windows to let any daylight in. 610 00:29:39,695 --> 00:29:42,363 Using computational acoustics modeling 611 00:29:42,364 --> 00:29:43,864 and careful reenactments, 612 00:29:43,865 --> 00:29:47,744 a team of experts makes an astonishing discovery. 613 00:29:49,621 --> 00:29:50,705 These chambers were likely built 614 00:29:50,706 --> 00:29:52,248 with one thing in mind: sound. 615 00:29:52,249 --> 00:29:55,042 Analyses have found that sound waves travel extremely quickly 616 00:29:55,043 --> 00:29:57,545 down the narrow passages, bouncing off the walls 617 00:29:57,546 --> 00:30:00,006 to fill the adjoining alcoves and galleries. 618 00:30:00,007 --> 00:30:02,049 The effect would have been quite dramatic. 619 00:30:02,050 --> 00:30:05,052 Music or human voices would effortlessly fill the space 620 00:30:05,053 --> 00:30:06,554 with little to no echo, 621 00:30:06,555 --> 00:30:09,265 meaning that even if you were standing far from the source, 622 00:30:09,266 --> 00:30:11,892 you could hear incredibly clearly. 623 00:30:11,893 --> 00:30:13,811 The architecture of the tunnels would have allowed 624 00:30:13,812 --> 00:30:17,398 the Chavín to project this sound out of the building itself 625 00:30:17,399 --> 00:30:20,985 to pilgrims in the plaza outside. 626 00:30:20,986 --> 00:30:24,697 In effect, the entire building would have seemed alive. 627 00:30:24,698 --> 00:30:27,450 We can't be sure exactly what these Chavín ceremonies 628 00:30:27,451 --> 00:30:30,036 sounded like, but excavations have uncovered 629 00:30:30,037 --> 00:30:33,581 several ancient trumpets made out of conch shells 630 00:30:33,582 --> 00:30:36,710 that we've actually been able to reproduce and record. 631 00:30:38,920 --> 00:30:41,255 The intense soundscapes from the galleries 632 00:30:41,256 --> 00:30:42,465 weren't the only way 633 00:30:42,466 --> 00:30:45,760 the Chavín enhanced their ritual experiences. 634 00:30:45,761 --> 00:30:49,597 Bone tubes that were once used to inhale psychoactive plants 635 00:30:49,598 --> 00:30:52,767 have also been found in these galleries. 636 00:30:52,768 --> 00:30:56,604 The combination of ritual drug use and elaborate soundscapes 637 00:30:56,605 --> 00:31:00,483 would have made for a truly otherworldly experience. 638 00:31:00,484 --> 00:31:02,651 So could the chambers at Tierradentro 639 00:31:02,652 --> 00:31:05,654 have served a similar ritual purpose? 640 00:31:05,655 --> 00:31:07,031 Based on the existing evidence, 641 00:31:07,032 --> 00:31:10,284 the chambers of Tierradentro don't appear to have been carved 642 00:31:10,285 --> 00:31:12,203 with acoustics in mind. 643 00:31:12,204 --> 00:31:15,831 There are no plazas to host crowds of pilgrims, 644 00:31:15,832 --> 00:31:19,794 and to date, there's no evidence of ritual drug use either. 645 00:31:19,795 --> 00:31:22,588 But there are signs that these were places 646 00:31:22,589 --> 00:31:25,966 of profound spiritual importance. 647 00:31:25,967 --> 00:31:27,426 A closer look at the architecture 648 00:31:27,427 --> 00:31:31,472 of the Tierradentro chambers reveals their true function. 649 00:31:31,473 --> 00:31:32,932 Most of the Tierradentro structures 650 00:31:32,933 --> 00:31:34,892 have a central staircase or shaft 651 00:31:34,893 --> 00:31:36,852 that leads down into a main chamber, 652 00:31:36,853 --> 00:31:40,648 which is surrounded by a series of side alcoves or niches. 653 00:31:40,649 --> 00:31:42,650 These impressive underground burial spaces 654 00:31:42,651 --> 00:31:45,069 are known today as hypogea. 655 00:31:45,070 --> 00:31:47,446 These were grand collective tombs. 656 00:31:47,447 --> 00:31:51,742 So instead of just one person, entire elite families or clans 657 00:31:51,743 --> 00:31:54,745 could be buried together in the same space. 658 00:31:54,746 --> 00:31:56,705 Grave offerings were left with the bodies, 659 00:31:56,706 --> 00:32:00,126 including gold ornaments, ceramic pottery 660 00:32:00,127 --> 00:32:01,669 and stone statues, 661 00:32:01,670 --> 00:32:05,006 underscoring just how important these people were. 662 00:32:06,842 --> 00:32:09,844 Sadly, over the centuries, many of these tombs 663 00:32:09,845 --> 00:32:14,181 were looted and most of the original objects are now gone. 664 00:32:14,182 --> 00:32:16,183 But some artwork remains. 665 00:32:16,184 --> 00:32:20,855 Bold black, red and white lines zigzag and spiral their way 666 00:32:20,856 --> 00:32:25,359 across the walls in intricate geometric designs. 667 00:32:25,360 --> 00:32:29,655 Some of the murals appear to depict animal and human forms. 668 00:32:29,656 --> 00:32:31,824 It's possible that these represented gods 669 00:32:31,825 --> 00:32:33,534 or guardians of some sort. 670 00:32:33,535 --> 00:32:37,830 But their true symbolic meaning remains a mystery. 671 00:32:37,831 --> 00:32:40,166 Work is still underway at Tierradentro, 672 00:32:40,167 --> 00:32:43,586 where archaeologists continue to piece together the story 673 00:32:43,587 --> 00:32:45,754 of a civilization that left behind 674 00:32:45,755 --> 00:32:49,551 only its extraordinary, ornate tombs. 675 00:33:02,480 --> 00:33:04,982 180 miles northwest of London, 676 00:33:04,983 --> 00:33:06,984 Liverpool stands as one of Britain's 677 00:33:06,985 --> 00:33:10,529 most historically significant seaports. 678 00:33:10,530 --> 00:33:12,573 Liverpool was founded in 1207, 679 00:33:12,574 --> 00:33:14,408 when King John granted a charter 680 00:33:14,409 --> 00:33:16,827 for a new town on the River Mersey. 681 00:33:16,828 --> 00:33:19,455 {\an8}Now, early trade with Ireland helped it grow, 682 00:33:19,456 --> 00:33:20,831 but by the 18th century 683 00:33:20,832 --> 00:33:23,876 {\an8}it had become a hub of transatlantic commerce. 684 00:33:23,877 --> 00:33:25,252 {\an8}And there's a dark side to that. 685 00:33:25,253 --> 00:33:28,464 {\an8}There was this trade system called the Liverpool Triangle, 686 00:33:28,465 --> 00:33:30,841 {\an8}in which manufactured goods from Liverpool 687 00:33:30,842 --> 00:33:34,094 {\an8}were sent to West Africa to be traded for enslaved people, 688 00:33:34,095 --> 00:33:37,056 and those enslaved people went across the Atlantic 689 00:33:37,057 --> 00:33:38,098 to the West Indies, 690 00:33:38,099 --> 00:33:41,769 where they were traded for sugar and other crops. 691 00:33:41,770 --> 00:33:43,938 The 19th century brought explosive growth. 692 00:33:43,939 --> 00:33:46,899 {\an8}The Liverpool and Manchester Railway opened in 1830, 693 00:33:46,900 --> 00:33:49,276 {\an8}the world's first commercial passenger line. 694 00:33:49,277 --> 00:33:53,113 The Albert Dock followed in 1846 with fireproof warehouses 695 00:33:53,114 --> 00:33:56,659 and hydraulic cranes that cut ship turnaround time in half. 696 00:33:56,660 --> 00:33:58,869 During the Irish Famine, thousands arrived by ship, 697 00:33:58,870 --> 00:34:03,791 and by midcentury, Liverpool was known as the New York of Europe. 698 00:34:03,792 --> 00:34:05,000 In the 20th century, 699 00:34:05,001 --> 00:34:07,878 Liverpool faced disruption and decline. 700 00:34:07,879 --> 00:34:11,590 {\an8}Its port made it a target during both World Wars, 701 00:34:11,591 --> 00:34:14,718 {\an8}and the city was hit hard during the Blitz. 702 00:34:14,719 --> 00:34:17,972 Post-war, the city faced economic depression, 703 00:34:17,973 --> 00:34:21,141 but Liverpool remained culturally vital 704 00:34:21,142 --> 00:34:22,559 from the Three Graces-- 705 00:34:22,560 --> 00:34:24,979 iconic buildings located at the waterfront-- 706 00:34:24,980 --> 00:34:27,564 to the global explosion of music and identity 707 00:34:27,565 --> 00:34:30,150 that came with the Beatles. 708 00:34:30,151 --> 00:34:33,612 In 2001, a small team cuts through the roof 709 00:34:33,613 --> 00:34:34,863 of a buried cellar 710 00:34:34,864 --> 00:34:37,574 in the Paddington District of Liverpool. 711 00:34:37,575 --> 00:34:39,910 Lowered in by harness, they find themselves 712 00:34:39,911 --> 00:34:42,121 in a rubble-choked chamber, 713 00:34:42,122 --> 00:34:46,000 an upper level of a long lost passage. 714 00:34:46,001 --> 00:34:47,751 {\an8}Over the next two decades, 715 00:34:47,752 --> 00:34:51,755 {\an8}volunteers cleared tons of soil, ash and debris, 716 00:34:51,756 --> 00:34:53,716 revealing a hidden network 717 00:34:53,717 --> 00:34:57,970 of at least 15 chambers carved into sandstone. 718 00:34:57,971 --> 00:35:00,180 Some are narrow crawlspaces, 719 00:35:00,181 --> 00:35:03,559 just four feet wide and six feet high. 720 00:35:03,560 --> 00:35:05,686 Others are far more dramatic, 721 00:35:05,687 --> 00:35:07,813 like the vaulted banqueting hall, 722 00:35:07,814 --> 00:35:10,941 and measuring roughly 64 feet long, 723 00:35:10,942 --> 00:35:15,988 14 feet wide and 27 feet high. 724 00:35:15,989 --> 00:35:22,703 It reportedly connects to more than two dozen other tunnels. 725 00:35:22,704 --> 00:35:24,496 Paddington is one of the deepest parts 726 00:35:24,497 --> 00:35:25,789 of the network. 727 00:35:25,790 --> 00:35:28,500 It's this stacked complex of at least three levels, 728 00:35:28,501 --> 00:35:31,712 dropping 56 feet below ground. 729 00:35:31,713 --> 00:35:33,839 Brick pillars sit on sandstone supports, 730 00:35:33,840 --> 00:35:35,966 and according to one old account, 731 00:35:35,967 --> 00:35:38,844 the layout runs deeper than the four-story building 732 00:35:38,845 --> 00:35:41,805 that once stood above. 733 00:35:41,806 --> 00:35:44,183 For decades, the tunnels were mostly rumor, 734 00:35:44,184 --> 00:35:47,061 until a rediscovered 1925 newspaper article 735 00:35:47,062 --> 00:35:48,937 described a man walking underground 736 00:35:48,938 --> 00:35:51,398 for over a mile beneath the streets, 737 00:35:51,399 --> 00:35:53,150 reigniting public interest. 738 00:35:53,151 --> 00:35:56,070 Earlier maps and surveys have recorded parts of the system, 739 00:35:56,071 --> 00:35:58,697 but later construction buried much of it. 740 00:35:58,698 --> 00:36:00,157 It wasn't until the mid '90s 741 00:36:00,158 --> 00:36:03,410 that official archaeological investigation began. 742 00:36:03,411 --> 00:36:07,956 Computer scans now show over 460,000 square feet 743 00:36:07,957 --> 00:36:09,958 of map excavations, 744 00:36:09,959 --> 00:36:13,253 spreading underground in a spider-like pattern. 745 00:36:13,254 --> 00:36:16,507 But the full extent of the tunnels is still unknown. 746 00:36:16,508 --> 00:36:20,594 So what kind of purpose or obsession could justify 747 00:36:20,595 --> 00:36:23,263 building a hidden world beneath the city? 748 00:36:23,264 --> 00:36:25,391 Inside the tunnels, scattered artifacts 749 00:36:25,392 --> 00:36:28,227 raise questions about their possible use 750 00:36:28,228 --> 00:36:31,188 and who was moving through them. 751 00:36:31,189 --> 00:36:33,899 These tunnels don't look like spaces 752 00:36:33,900 --> 00:36:36,902 that were simply quarried and left behind. 753 00:36:36,903 --> 00:36:40,280 Excavations have uncovered hundreds of artifacts 754 00:36:40,281 --> 00:36:44,368 like glass whiskey bottles and stoneware jars. 755 00:36:44,369 --> 00:36:48,288 Given the volume and variety, is it possible these tunnels 756 00:36:48,289 --> 00:36:54,129 supported contraband movement or some form of underground trade? 757 00:36:56,297 --> 00:36:57,715 In the late 1700s and early 1800s, 758 00:36:57,716 --> 00:37:00,843 smuggling was rampant across Britain, 759 00:37:00,844 --> 00:37:03,137 and it was fueled by high taxes 760 00:37:03,138 --> 00:37:06,807 on things like tea, tobacco and booze. 761 00:37:06,808 --> 00:37:10,060 What began as a small-scale evasion 762 00:37:10,061 --> 00:37:13,480 grew into a full-blown underground industry. 763 00:37:13,481 --> 00:37:17,401 Smuggled spirits may have at times outnumbered 764 00:37:17,402 --> 00:37:20,320 the legal shipments coming through London's docks. 765 00:37:20,321 --> 00:37:23,073 Whole communities even came up that rely entirely 766 00:37:23,074 --> 00:37:26,493 on the economic benefits of smuggling. 767 00:37:26,494 --> 00:37:27,995 Beneath Liverpool, some of the tunnels 768 00:37:27,996 --> 00:37:29,997 are blocked or collapsed, 769 00:37:29,998 --> 00:37:31,832 but they may have once linked to larger features 770 00:37:31,833 --> 00:37:33,041 like the Great Tunnel, 771 00:37:33,042 --> 00:37:35,961 a vast chamber documented in the 19th century. 772 00:37:35,962 --> 00:37:38,338 In the 2000s, researchers drilled into the site 773 00:37:38,339 --> 00:37:42,009 in an attempt to relocate it, but found nothing conclusive. 774 00:37:42,010 --> 00:37:44,678 If the tunnel still exists, it could suggest the network 775 00:37:44,679 --> 00:37:47,139 was once organized around a central hub, 776 00:37:47,140 --> 00:37:51,185 built to move discreetly between different areas. 777 00:37:51,186 --> 00:37:54,438 Just northwest of Liverpool in New Brighton, 778 00:37:54,439 --> 00:37:57,191 a different underground network reveals how tunnels 779 00:37:57,192 --> 00:38:01,361 could support large scale, secretive operations. 780 00:38:01,362 --> 00:38:04,448 During World War II, New Brighton's Seaside Arcade 781 00:38:04,449 --> 00:38:08,994 concealed a full-scale munitions factory below ground. 782 00:38:08,995 --> 00:38:12,039 The tunnels, said to be around 100 years old at the time, 783 00:38:12,040 --> 00:38:16,043 were cleared and converted to house up to 200 women, 784 00:38:16,044 --> 00:38:20,088 producing more than 250,000 bullets and shell casings 785 00:38:20,089 --> 00:38:25,052 a week, all while the arcade above kept up appearances. 786 00:38:25,053 --> 00:38:27,387 The operation was such a secret 787 00:38:27,388 --> 00:38:31,558 that even Nazi bombing maps failed to pick up the factory 788 00:38:31,559 --> 00:38:32,684 beneath the arcade. 789 00:38:32,685 --> 00:38:38,440 By 1943, the site also served as a U.S. ordnance base, 790 00:38:38,441 --> 00:38:41,151 assembling vehicles and repairing equipment 791 00:38:41,152 --> 00:38:43,153 from the Normandy front. 792 00:38:43,154 --> 00:38:48,576 It was a vast covert network right under the public's feet. 793 00:38:50,370 --> 00:38:53,121 So the New Brighton tunnels show that older spaces 794 00:38:53,122 --> 00:38:55,082 could be adapted for covert use. 795 00:38:55,083 --> 00:38:57,543 But there's no evidence that the Liverpool tunnels 796 00:38:57,544 --> 00:39:00,254 were built for this or repurposed for this. 797 00:39:00,255 --> 00:39:04,049 After 1815, the economics of smuggling collapsed 798 00:39:04,050 --> 00:39:05,926 as coastal blockades strengthened, 799 00:39:05,927 --> 00:39:07,386 and free trade policies took hold, 800 00:39:07,387 --> 00:39:09,638 it just didn't make economic sense anymore. 801 00:39:09,639 --> 00:39:12,683 And by the time the excavation began in Liverpool, 802 00:39:12,684 --> 00:39:14,393 smuggling was already in decline. 803 00:39:14,394 --> 00:39:19,648 So these tunnels were built for a different purpose. 804 00:39:19,649 --> 00:39:21,483 Other artifacts suggest the tunnels 805 00:39:21,484 --> 00:39:25,445 may have been designed to sustain a long-term vision. 806 00:39:25,446 --> 00:39:27,447 In ways, these spaces seem designed 807 00:39:27,448 --> 00:39:29,074 with daily life in mind. 808 00:39:29,075 --> 00:39:31,952 Excavations have uncovered bed warmers, chamber pots, 809 00:39:31,953 --> 00:39:34,121 infant feeding bottles, toothbrushes, 810 00:39:34,122 --> 00:39:38,250 children's toys, and, chillingly, bottles of poison. 811 00:39:38,251 --> 00:39:41,003 More than 100 years of rubbish was found in the tunnels, 812 00:39:41,004 --> 00:39:43,672 some dating to a period shaped by religious upheaval 813 00:39:43,673 --> 00:39:45,132 and apocalyptic belief. 814 00:39:45,133 --> 00:39:47,384 Is it possible these spaces were meant for life to continue 815 00:39:47,385 --> 00:39:50,804 underground after everything above it ended? 816 00:39:50,805 --> 00:39:52,139 The early 19th century 817 00:39:52,140 --> 00:39:54,975 was steeped in apocalyptic belief. 818 00:39:54,976 --> 00:39:57,394 Movements like Millerism took hold, 819 00:39:57,395 --> 00:39:59,730 convincing tens of thousands of followers 820 00:39:59,731 --> 00:40:02,482 across the U.S., Canada and Britain 821 00:40:02,483 --> 00:40:07,362 that Christ would return by 1844 to cleanse the world. 822 00:40:07,363 --> 00:40:10,324 In that kind of climate, digging a refuge underground 823 00:40:10,325 --> 00:40:12,951 wouldn't have seemed irrational at all; 824 00:40:12,952 --> 00:40:14,328 it might have felt urgent. 825 00:40:14,329 --> 00:40:16,705 Roughly 2,000 miles from Liverpool, 826 00:40:16,706 --> 00:40:20,083 in the village of Nikolskoe in western Russia, 827 00:40:20,084 --> 00:40:23,211 another underground structure was built to outlast 828 00:40:23,212 --> 00:40:26,298 what its creators believed was coming above. 829 00:40:26,299 --> 00:40:30,802 In 2007, a Russian doomsday sect vanished, 830 00:40:30,803 --> 00:40:32,930 only to be found living in a bunker, 831 00:40:32,931 --> 00:40:36,058 excavated more than 30 feet deep 832 00:40:36,059 --> 00:40:40,062 into the snow-covered clay and rock of Nikolskoe. 833 00:40:40,063 --> 00:40:41,563 The group had threatened to blow themselves up 834 00:40:41,564 --> 00:40:44,149 with gas canisters if forced above ground. 835 00:40:44,150 --> 00:40:45,692 But when the roof eventually gave way, 836 00:40:45,693 --> 00:40:49,363 some took it as a sign from God and climbed out. 837 00:40:49,364 --> 00:40:51,073 The scene inside was haunting. 838 00:40:51,074 --> 00:40:53,283 Sleeping spaces padded with cardboard, 839 00:40:53,284 --> 00:40:55,202 a kitchen carved into the rock, 840 00:40:55,203 --> 00:40:57,704 and walls etched with drawings of flowers and trees. 841 00:40:57,705 --> 00:41:01,042 Even a chess set and children's books were left behind. 842 00:41:02,543 --> 00:41:05,003 While Liverpool's tunnels and Nikolskoe 843 00:41:05,004 --> 00:41:06,922 contain interesting artifacts, 844 00:41:06,923 --> 00:41:09,675 and do share certain architectural traits, 845 00:41:09,676 --> 00:41:12,886 the underlying context is entirely different. 846 00:41:12,887 --> 00:41:14,680 Nikolskoe's underground network was built 847 00:41:14,681 --> 00:41:17,641 with a clear, apocalyptic religious mindset, 848 00:41:17,642 --> 00:41:20,060 but there's no evidence of that kind of belief system 849 00:41:20,061 --> 00:41:21,311 in Liverpool. 850 00:41:21,312 --> 00:41:22,521 The motive here seems rooted 851 00:41:22,522 --> 00:41:25,440 in a different kind of long-term goal. 852 00:41:25,441 --> 00:41:26,733 In the heart of Liverpool's 853 00:41:26,734 --> 00:41:29,236 19th century industrial boom, 854 00:41:29,237 --> 00:41:31,405 a strange pattern of construction 855 00:41:31,406 --> 00:41:34,074 points back to a single figure. 856 00:41:34,075 --> 00:41:37,452 In the early 1800s, Joseph Williamson, 857 00:41:37,453 --> 00:41:40,497 a wealthy, eccentric tobacco merchant, 858 00:41:40,498 --> 00:41:43,291 began developing land in the area. 859 00:41:43,292 --> 00:41:46,420 He modified houses with bricked-up windows, 860 00:41:46,421 --> 00:41:48,463 but the work didn't stop there. 861 00:41:48,464 --> 00:41:51,633 His crews kept digging, deeper and farther, 862 00:41:51,634 --> 00:41:56,304 creating a vast tunnel network with no clear purpose. 863 00:41:56,305 --> 00:42:01,435 Williamson's name soon became inseparable from the tunnels. 864 00:42:01,436 --> 00:42:04,396 But what compelled him to keep going? 865 00:42:04,397 --> 00:42:07,149 By 1815, the Napoleonic Wars had ended, 866 00:42:07,150 --> 00:42:10,193 and Liverpool was flooded with all these soldiers 867 00:42:10,194 --> 00:42:12,946 coming back with limited job options. 868 00:42:12,947 --> 00:42:16,074 Now, by then, Williamson had sold his tobacco business. 869 00:42:16,075 --> 00:42:19,786 So he started hiring all these soldiers to dig. 870 00:42:19,787 --> 00:42:21,413 And for a lot of them, 871 00:42:21,414 --> 00:42:24,750 that digging was the only steady source of income 872 00:42:24,751 --> 00:42:27,586 in a time when there was just no other work. 873 00:42:27,587 --> 00:42:30,005 As time went on, the tunnels grew deeper, 874 00:42:30,006 --> 00:42:32,507 more complex, and more aimless. 875 00:42:32,508 --> 00:42:35,343 Some twist, stack, or lead nowhere at all. 876 00:42:35,344 --> 00:42:38,472 Men worked by candlelight with picks, shovels, and barrows, 877 00:42:38,473 --> 00:42:40,766 while carpenters used axes and saws. 878 00:42:40,767 --> 00:42:42,100 It's possible that the project 879 00:42:42,101 --> 00:42:44,352 was less about utility and architecture, 880 00:42:44,353 --> 00:42:45,604 than it was hands-on training 881 00:42:45,605 --> 00:42:47,647 in trades like masonry and bricklaying. 882 00:42:47,648 --> 00:42:50,525 If so, the tunnel's true value wasn't in their purpose, 883 00:42:50,526 --> 00:42:53,028 but in the livelihoods they built. 884 00:42:53,029 --> 00:42:54,237 There are all kinds of theories 885 00:42:54,238 --> 00:42:56,031 about Williamson's tunnels, 886 00:42:56,032 --> 00:42:58,992 but he left no blueprints or explanation. 887 00:42:58,993 --> 00:43:00,994 After his wife died in 1822, 888 00:43:00,995 --> 00:43:03,371 he added domestic style chambers, 889 00:43:03,372 --> 00:43:05,373 even a grand banquet hall. 890 00:43:05,374 --> 00:43:08,752 For a man with no financial need and no defined purpose, 891 00:43:08,753 --> 00:43:13,424 the tunnels may have become both his obsession and his escape. 892 00:43:16,177 --> 00:43:19,137 Some argue the so-called passages 893 00:43:19,138 --> 00:43:22,390 likely began as open sandstone quarries, 894 00:43:22,391 --> 00:43:24,726 then covered and built over. 895 00:43:24,727 --> 00:43:29,523 So in that view, Williamson wasn't digging aimlessly. 896 00:43:29,524 --> 00:43:32,526 He was reclaiming scarred land 897 00:43:32,527 --> 00:43:35,362 {\an8}and turning it into something profitable. 898 00:43:35,363 --> 00:43:38,573 {\an8}But that still doesn't explain the scale, 899 00:43:38,574 --> 00:43:40,742 {\an8}the chambers, and the banquet hall. 900 00:43:40,743 --> 00:43:43,453 {\an8}If it started as a quarry restoration, 901 00:43:43,454 --> 00:43:48,708 {\an8}it became something else and something much harder to define. 902 00:43:48,709 --> 00:43:50,210 {\an8}Hidden beneath Liverpool, 903 00:43:50,211 --> 00:43:52,337 {\an8}Williamson's tunnels remain a puzzle 904 00:43:52,338 --> 00:43:54,548 {\an8}of purpose and persistence, 905 00:43:54,549 --> 00:43:56,925 {\an8}a testament to relentless effort 906 00:43:56,926 --> 00:43:58,593 {\an8}and to the blurred line 907 00:43:58,594 --> 00:44:02,431 {\an8}between visionary intent and personal obsession.