Original subtitles

To the average person, it might not look like anything,

but there are actually five separate shipwrecks here.

- This could be the most important maritime discovery

of the century, or possibly of all time.

[narrator] A tiny remote island in the middle of the Pacific

is under attack.

Yellow crazy ants aren't the most toxic

or dangerous thing on this island.

[narrator] A bizarre discovery in a small Micronesian island

may be far more valuable than first imagined.

- It's extraordinary.

They're on the beaches, on the pathways,

and in the deep forest.

- There are dozens of them.

What are these things?

[narrator] Isolated, scarce on resources, islands

are worlds unto themselves.

Bizarre creatures, ancient gods, and haunting ruins.

Baffling murders and deadly spirits.

What will be discovered on Earth's mysterious islands?

♪ ♪

[narrator] Goat Island sits at Narragansett Bay,

an inlet on the northeastern coast of Rhode Island in the US.

- Goat Island is a small, narrow strip of land

just off the coast of the city of Newport.

The island's name is likely due to the fact

that early Newport colonists used

the island as a goat pasture.

The town was founded in 1639 and eventually established itself

as one of the busiest ports in the

North American British colonies.

- The port has been such a destination over the centuries

that Rhode Island's coastline is littered with shipwrecks.

[narrator] In 2019, maritime archaeologists investigating

shipwrecks in the harbor are using sonar to survey

an area between 800 to 2,600 feet off the

northern tip of Goat Island when they spot something strange.

To the average person, it might not look like anything,

but there are actually five separate shipwrecks here.

Given the region's history, that isn't too surprising.

However, the positioning of these ships are strange.

They're lined up in a near perfect row,

one after the other.

How is that possible?

Buried beneath silt and sediment,

the ships are lying in a generally southern direction

with as little as 164 feet between them.

It's very odd.

They're almost too orderly to even be considered shipwrecks,

vessels that crashed in the harbor and sank.

There might be another explanation.

Could this be an artificial reef?

[narrator] An artificial reef is a man-made structure

that mimics natural coral reef structures in the ocean.

They are created in areas that have lost

or have damaged natural reefs and require new structure

for the protection of marine life and seascapes.

[Alison Leonard] While artificial reefs do exist in

Rhode Island, the first one was constructed in 2019.

Only this wasn't made of old ships,

but 64, 1,300-pound concrete domes, known as reef balls.

So what happened to these ships?

[narrator] Needing more information, the team

gears up and takes to the water to explore the site.

They collect images and samples of stone, coal, timber,

and sediment for analysis.

[Anthea Nardi] These are very difficult conditions.

The waters are cold, and visibility

is at best three feet and as poor as only a few inches.

But it's obvious that the wrecks have been here

for a long, long time.

And where elements of the wrecks are closer to the surface,

you can see that they're made from wood.

[narrator] Much of the wood has been degraded over time

due to the water logging, erosion, and marine organisms.

But analysis of timber samples collected from the site

helps the marine archaeologists narrow down

the origin of the ships.

[Anthony Cantor] The timbers include planks of a British

variety of white oak and elm.

This is interesting, as it suggests

that the ships could have originated

in a British shipyard.

[narrator] The team focused their effort on the largest of

the five ships, whose remains lie within an

area approximately 60 feet long and 24 feet wide.

The archaeologists identify and examine

the number of artifacts from the site

including ballast stones, weights,

used to balance a ship, and something even more exciting.

It's a cannon, and not just one.

There are four cannons poking up from the sea floor of the site.

Two lie on the western edge and are over five feet long.

Another sits to the south, and the last

is halfway down the ship's length

on the eastern edge of the site.

This is a huge discovery.

[Anthea Nardi] This is no casual marine find.

If a cannon was aboard any of these ships,

let alone four cannons, then it's more than likely

that this is a naval vessel.

And if that's the case, maybe these ships

were sunk in a battle.

[narrator] In the mid-18th century,

tensions were building between the 13 American colonies

and the British Empire.

Overtaxed and heavily controlled,

the colonies united in a revolution against the crown

that would last from 1775 to 1783,

as they battled for independence.

[Alison Leonard] In 1776, British forces seized

the town of Newport and the entirety of Rhode Island.

Newport's strategic location allowed the British Navy

to potentially blockade major colonial ports like New York,

Boston, and Philadelphia, all of which

were essential for the colonial war effort.

[James Ellis] But the French had other plans.

In 1778, they entered the war in support of the American rebels

and promptly sent a fleet to Newport to try and drive

the British out.

So could these ships lying at the bottom of the harbor

be casualties of this battle?

[narrator] In the search for answers,

the archaeologists begin careful excavation of the

largest of the five shipwrecks and make a bizarre discovery.

While uncovering the elements of the hull structure,

a clear hole is found on the side of the ship.

It's large and oval in shape,

measuring 10 and 1/2 by 6 and 1/2 inches.

[Anthony Cantor] This is not battle damage of any kind.

In fact, the wood shows signs of heavy and repeated blows

by tools, maybe a crowbar or an ax.

This hole was cut into the ship's hull intentionally.

Why would someone do that?

[James Ellis] There's another hole discovered toward the stern of the ship,

and it too has clear evidence of tool marks.

The holes match with other known scuttled British ships

from the time period.

[narrator] The act of scuttling a ship

means to intentionally sink or destroy it.

It can be done using valves or hatches, explosive

or friendly fire, or by cutting holes into the hull.

It's a practice performed to dispose of old, damaged,

or captured ships, or as an act of preservation

to destroy the ship before capture by enemies.

Looking for answers, the team turns to the

British Naval Archives for reports regarding the war effort

and finds a very informative document and map.

The map outlines British defensive plans.

It seems that as the French fleet approached in 1778,

the British, desperate to avoid losing

their strategic position, scuttled 13 ships

to prevent them from falling into enemy hands.

[Anthea Nardi] They also hope that the ship's

structures would be obstacles to block

French vessels from approaching Newport Harbor.

So these five must be among the list of

the scuttled British vessels.

[narrator] In a letter from Lieutenant John Knowles,

the agent for transports in Newport,

to the Navy board on 12 September, 1778,

he confirms that five ships-- the Lord Sandwich, the

Earl of Orford, the Yoward, the Peggy, and the Mayflower--

were sunk off the northern tip of Goat Island.

The Earl of Orford is an American-built ship,

so it can't be the large wreck we're looking at.

The Mayflower is a British-made transport

vessel that carried troops and equipment to Newport,

but it can't be the Mayflower either.

[Anthony Cantor] When it comes to the Peggy,

this was actually a relatively common ship name.

It's most likely that the Peggy that

was sunk at Newport in August of 1778

was an American-built, single-decked, mid-sized vessel,

so not this wreck either.

[Anthea Nardi] So the mysterious, large,

four-cannon, British-built shipwreck is either the

Yoward or the Lord Sandwich.

Both vessels are registered as British-made.

However, the Lord Sandwich is over 100 tons larger

than the Yoward, which has a 250-ton capacity.

So the largest excavated wreck off the northern tip of

Goat Island is the Lord Sandwich.

[narrator] In November of 1776,

the Lord Sandwich arrived in Newport with

574 German mercenaries hired by the British crown to

fight the American rebels.

[James Ellis] After the ship arrived at Newport,

the Lord Sandwich was converted to a prison ship

anchored in the harbor.

Then, as its final act, the ship was intentionally

sunk along with five other ships as a line of defense

to protect the town.

But why sacrifice such a large and impressive ship?

Was it damaged or run down?

[narrator] Searching for answers,

the team again turns to the archive

and discovers a strange and exciting piece of history.

It appears that the Lord Sandwich

was a new name for an old ship that was sold

to a private investor in 1776.

When the war broke out, that investor

offered the ship under its new name to the British Navy.

And after a patch and repair, it was accepted.

[narrator] A ledger known as Lloyd's Register from

1776 and 1777 notes the Lord Sandwich's original name.

The original name of this ship is

one of the most famous names in naval history, the Endeavor.

This could be the most important maritime discovery

of the century or possibly of all time.

- The Endeavor's captain was James Cook,

the famed 18th century British naval captain and navigator.

He was one of the most prolific naval explorers in history

until his death in 1779 in the Kingdom of Hawaii.

While on the Endeavor, Cook's mapping and claiming

of New Zealand and the east coast of Australia

on behalf of King George III between 1768 and 1771

changed the course of the region's history

for better and for worse.

- With the passage of time and the storied

history of the Endeavor, it's likely that most of

the unfixed items that were once part of the ship

have been lost or replaced.

So the team will need to examine the ship's structure

to solve this puzzle.

[narrator] In 2019, the team returns to the site for another

dive and discovers something that may help conclusively prove

that the Lord Sandwich and the Endeavor are the same ship

once and for all.

[James Ellis] It's the remains of the ship's bilge pump well,

a crucial system for managing the water that collects

in the bottom of boats.

The pump removes this water and sends it overboard.

It might not sound exciting, but this is a key piece

of the ship's design.

- When you look at the British Admiralty survey of the vessel

from 1768 and superimpose the location of the pump well

over archival drafts of the Endeavor,

the pump wells are a perfect match.

[narrator] This matching allows the archaeologists

to use predictive modeling, a technique where known data is

used to predict unknown aspects of the site

to locate other parts of the ship.

And in a 2021 dive, they made another remarkable discovery.

- They found a very unique joint in the bow area of the ship.

This joint, called the half-lap scarf,

is crucial for connecting two timber pieces end to end,

and it's essential in shipbuilding.

The only other half-lap scarf joint on record

from the 18th century is recorded in ship plans

held at the National Maritime Museum in Greenwich, England.

And they're from a ship built by the same shipbuilder

as the Endeavor.

Another match.

[Anthony Cantor] Incredibly, the Endeavor,

a ship that many marine enthusiasts

and archaeologists have been searching for for decades,

has been lying at the bottom of Narragansett Bay

for nearly 250 years.

Now its storied history has a final chapter.

[narrator] Today, Goat Island is home to marinas and hotels,

where people come from far and wide

to enjoy the scenic views and rich history of the region.

With the famed Endeavor being added

to the thousands of sunken vessels in the waters

off Rhode Island, surely this site

will be a draw for marine history buffs and divers

from all over the world.

Deep into the Pacific Ocean, about 700 nautical miles

southwest of Hawaii, lies a US territory,

a cluster of four small islands called Johnston Atoll.

- These tiny islands are uninhabited by humans,

but have a massive bird presence,

which is why they are collectively a

protected national wildlife refuge.

Johnston Atoll is a haven for hundreds of thousands

of migrating shorebirds and nesting seabirds.

[Anthony Cantor] These tiny islands are so remote,

it takes three days to get here by boat on open water

from Honolulu.

This is one of the most isolated patches of land on the planet,

and it feels like it's in the middle of nowhere.

- That's why these islands are so valuable to seabirds.

Long distance flyers like the Black-footed albatross,

the Laysan albatross, they journey all over the Pacific

and use places like this to stop, rest, and nest.

[narrator] In 2010, ornithologists are studying the

diminishing nest bird populations on the main island

and are entirely shocked by what they find.

- The birds of the island, like the red-tailed tropic birds,

are suffering a dangerous insect infestation.

Some are crawling with them, and others have been blinded.

What's going on here?

[Anthony Cantor] The ground looks like it's vibrating

with swarms of thin, yellowish-brown,

practically clear ants.

And the birds that nest on the ground

here are entirely overtaken by them.

[Dan Riskin] These are Anapolopus gracilipes,

or yellow crazy ants.

That is very bad.

They're called crazy ants because they have

these erratic defensive movements.

And while they don't bite or sting like other ants do,

they are able to spray formic acid to defend themselves

or to attack.

[narrator] Formic acid, named after ants themselves,

causes localized burning or irritation

on contact with skin or eyes and, over periods

of extended exposure, can be life-threatening to birds.

[James Ellis] Yellow crazy ants are actually one of the world's

top 100 most invasive species.

They are able to amass huge super colonies

with multiple queens and millions of workers, which

become threatening to any habitat, especially one

as remote as Johnston Atoll.

[Dan Riskin] In all likelihood, they were accidentally

moved around the world through the trade of produce

and materials by humans.

And these harmful but resilient ants

have spread throughout the Indo-Pacific.

By the 1990s, they were wreaking havoc far and wide

on tons of different islands.

[narrator] After reporting the issues to the authorities and

Parks Department, a team of experts is assembled to address

the situation and defend the birds.

They're called the Crazy Ant Strike Team.

- To eradicate the ants, insecticide-laced

cat food, corn syrup, and water are sprayed

along the infestation area.

The worker ants will then unknowingly

take the poisoned food back to their queens,

killing them and any future generations they may birth.

It is an effective tactic for ant elimination,

but it takes time and consistency.

[narrator] The strike team, members of the US Fish and

Wildlife Service, will stay on Johnston Atoll for six months.

But life here is no tropical paradise.

- This is a huge undertaking, so far from civilization

with no fresh water source or plumbing,

and nowhere to bathe other than the ocean.

Life here isn't just rough for the birds.

[narrator] While hunting ant colonies,

the team begins exploring the island.

And past the beach, thick palms, and vegetation,

they find traces of a strange past.

Through the brush and grasses, there

are remnants of massive stretches of pavement

cutting across the narrow island.

So many roads, but where do they lead?

[Anthony Cantor] Only it's not just old roads,

but something much, much larger.

Running down the center of the island for two miles,

practically its complete length, is a huge asphalt runway.

Why is there an airstrip all the way out here?

- Maybe the atoll was a refueling station.

You can imagine airlines may have needed access

to an emergency landing strip in case they ran into issues.

[James Ellis] However, modern airplanes,

even massive commercial aircraft like the Boeing 747,

can fly for 16 hours or 9,500 miles

without landing or refueling, which

could explain how this airstrip fell out of use.

But given the atoll's extremely remote location,

it seems an unlikely destination for commercial use at all.

Perhaps it has a military history.

[narrator] Records show that in 1934,

under President Franklin D. Roosevelt,

the atoll became a US Naval station.

And the island was a base for Naval and Air Forces

operations leading up to and during World War II.

It was a well-used refueling station.

But on December 7, 1941, this remote island

was drawn into something much larger

when the Japanese attacked the American Naval Base

at Pearl Harbor in Hawaii.

Johnston Atoll was shelled by the Japanese on

December 15th and 21st of 1941.

While this information does solve the question

about the runway and its purpose on the island,

it doesn't explain everything about this strange,

ant-infested birders' paradise.

[narrator] Exploring further, the team encounters

a bizarre, imposing structure that stands out

like a sore thumb along the horizon of the island.

The lone, multi-story building has an ominous appearance.

It's made of thick concrete, and it is entirely windowless.

[James Ellis] The now crumbling structure is heavily reinforced

and has none of the features you would expect if it were

associated with the runway, like a control tower.

And inside, there are strange signs

that detail how to have a decontamination shower.

What is this?

[narrator] Records state that this four-story building

is the Joint Operations Center, or JOC,

a control center for a nuclear testing operation.

In 1958, Johnston Atoll became the site of Cold War-era

nuclear weapons tests, and the island

was kept in a state of readiness for such uses until 1970.

In 1964, the JOC was built out of steel and thick layers

of concrete to withstand up to Category 4 hurricanes

and nuclear fallout, hence the 55 showerheads

for decontamination.

[James Ellis] During these tests,

there were a number of catastrophic failures.

The quick cleanup attempt from the failure of a test known

as Bluegill Prime resulted in radioactive waste being dumped

into a lagoon that subsequently polluted

the marine environment.

In the end, plutonium contamination

left radioactive pollution that still lingers today.

[narrator] Today, the shore is lined with a number of signs

warning against the consumption of fish or shellfish caught

in the waters off the island.

So it appears that yellow crazy ants

aren't the most toxic or dangerous thing on this island.

[narrator] After a long day of work combating the ants,

the team goes to their makeshift research facility.

But this is no regular laboratory.

- This is a bunker.

It's made of thick concrete and metal

with a sign that clearly reads,

"US government property, no trespassing."

Was this also built to support the nuclear testing?

- These days, the bunkers are filled with supplies

and used as temporary storage facilities

for the crazy ant strike team.

But a little research reveals that they

were likely added to the island in the 1970s

after nuclear testing was canceled.

So what were they used for?

[narrator] At the end of its nuclear era,

the US government converted over 40 acres of the tiny island

into heavy duty and highly sensitive storage that

included the construction of a series of concrete bunkers,

most of which are concentrated in the Red Hat Zone

of the south side of the island,

an area used to store chemical weapons.

- This tiny island stored over 6% of the total

US chemical stockpile, including every version of weapon designed

for a toxic chemical payload, including rockets, bombs,

and mines.

So there are crazed acid spewing ants, radioactive pollution,

and now chemical weapons?

What's up with this island?

[narrator] Everywhere the team goes, more of the bizarre

history of this deserted island is revealed.

Farther along a stretch of abandoned crumbling concrete,

there is yet another sign.

Only this one is a large official plaque.

[Anthony Cantor] The plaque identifies the site of the

Johnston Atoll chemical agent disposal system,

a massive incinerator.

It was constructed in 1985, just 15 years after the island

became a storage facility.

And by 1990, the incinerator was operational.

[James Ellis] Unfortunately, there were a number of

accidents and leaks tracked by the

Environmental Protection Agency along the way.

Ultimately, between 2001 and 2003,

the facility was shuttered, and the US Army

completed their cleanup and demolition of the site.

- Clearly, the yellow crazy ant infestation

was not the only threat to the birds and other wildlife

in this tropical paradise.

The military structures and the lingering contamination

are stark reminders of Johnston Atoll's dark history.

[narrator] 20 years have passed since the Army left the island

in the hands of the US Fish and Wildlife Services.

And since 2017, the Crazy Ant Strike Team

has not detected a single yellow crazy ant colony.

Now, slowly but surely, nature and the seabirds

are reclaiming the island for themselves.

Tucked within Conception Bay, just off Canada's North

Atlantic coast, is Bell Island, an 11-square-mile expanse

of relatively flat land bordered by redstone cliffs that

drop hundreds of feet into the ocean below.

- Although it's only about 12 miles northwest of St. John's,

the provincial capital of Newfoundland and Labrador,

and a mere 20-minute ferry ride from the mainland,

Bell Island feels like a world unto its own.

Today, the population of the island is roughly 2,200 people.

But there was a time when it was almost seven times that.

[narrator] In 2005, a team of divers is exploring

the frigid, murky depths near Lance Cove

off the southeastern shore of Bell Island

when they come across an astounding sight.

Lying on the ocean floor at a depth of around 150 feet,

there's a massive shipwreck.

What ship is this?

And how did it end up at the bottom of Conception Bay?

[Anthony Cantor] It's a pretty substantial vessel.

450 feet long.

It's fairly well preserved by the cold North Atlantic water.

But given the amount of marine life clinging to it,

it's clear that this vessel has been on the ocean floor

for a significant amount of time.

[narrator] Continuing to explore the exterior of the wreck

in search of clues as to the identity of the ship,

the team makes its way to the stern

and are shocked by what they find.

It's covered in anemones, but you can make out

what looks like a gun on the front deck of the ship.

So could this be a military vessel of some kind?

[Amma Wakefield] But there's only one gun on the stern.

If this was a military ship, there would be a lot more

and they would be positioned all over the decks.

[narrator] A short distance to the northeast of the shipwreck

overlooking Conception Bay,

a strange and somewhat ominous sight

greets any curious visitors to the area.

There are two large guns sitting on concrete platforms

pointing out over the water.

They're British-made QF Mark IVs with a barrel

length of 190 inches and a 4.7-inch diameter.

According to Canadian government archives,

installation of the guns began in the spring of 1940,

the year after Canada entered World War II.

So we've got a wrecked ship with a gun on its stern deck

on the bottom of the ocean off the coast

and two rather large guns positioned

overlooking the shoreline.

Clearly, something on Belle Island needed protecting.

But what?

- There's a flooded tunnel that extends over 1,000 feet,

leading from the island out under the seafloor

of Conception Bay.

And although there are plenty of

natural caves dotting these shores, this is a man-made

structure with concrete walls and reinforced ceilings.

What is this place?

[narrator] Swimming deeper into the claustrophobic murky depths,

braving frigid North Atlantic temperatures,

the team notices something odd on one of the walls.

- There's a small white cross etched into the concrete.

Not only that, they also find a drawing on the wall,

depicting a man with a pipe and beside him the name,

"James Bennett" is scrawled.

[narrator] Continuing through the darkness,

the team comes across several curious items

scattered haphazardly around the tunnel.

They find what looks to be a bucket sitting on the ground.

And a little further along, they discover a

broken wooden ladder leaning up against the

wall and some stray tools.

I think we can safely say that at some point,

this tunnel was not underwater.

[Sarah Klassen] There's an overturned cart lying on the

ground with its four wheels exposed.

They're metal with raised rims along the inside edges,

similar to a train's wheels.

This is an ore cart.

So what we're looking at here is an abandoned mine.

[narrator] Mining operations in Belle Island began in the 1890s

after the discovery of large, high-quality iron ore deposits,

a vital ingredient in the production of steel.

The island would eventually become

one of the world's leading suppliers of iron ore,

producing roughly 80 million tons.

In the early days, it was all surface mining.

But after a few years, they depleted those deposits

and were forced to go underground.

At first, they dug two subterranean mines

near the shoreline, but they quickly realized

that the real bonanza lay beneath

the seafloor of Conception Bay.

[narrator] Four offshore miners were dug under the Atlantic,

covering an astonishing 40 square miles

off the northern shore of Bell Island,

each one a labyrinth, running between three

and five miles in length and reaching as deep as

1,600 feet below the seafloor.

The working conditions were nothing short of horrific.

The miners worked 10 to 12-hour shifts,

six days a week for a pittance,

only seeing sunlight on Sundays.

And it was extremely dangerous.

In total, 106 men lost their lives in the mines.

They are commemorated by a number of white crosses

etched into the walls.

Despite the risks and hardships,

people were drawn to the island by the lure of steady work.

The population ballooned to as high as 15,000 at its peak,

But it didn't last.

- Starting in 1950, the mines began to

close one by one due to foreign competition,

and in 1966, the last one was shuttered.

The pumps that once kept it dry were turned off,

and the shafts were left to flood.

[narrator] Exiting the mine, the team decides to

have one last look around the shipwreck in

an attempt to identify her and determine how she ended

up on the ocean floor,

And what they find leaves them stunned.

There are two gaping holes in the ship's side,

one near the stern and one near the bow.

This must have been what brought her down,

but what could have caused such catastrophic damage?

[narrator] Probing the seafloor for clues around 130 feet from

the stern of the ship, the team makes a

shocking discovery.

There is a long, narrow, cylindrical piece

of metal debris resting on the ocean floor,

and if you look closely, you can make out a small

propeller on one end of it.

This is a torpedo.

This ship was attacked and sunk.

[narrator] In the early morning hours of November 2, 1942,

German submarine U-518 crept into Conception Bay

and fired two torpedoes at the SS Rose Castle,

a Canadian steamship loaded with iron ore

from Bell Island's mines destined to produce steel

for the Allied war efforts.

The Rose Castle went down in less than 90 seconds,

and 28 men perished.

But it didn't end there.

A second ore ship, the French steamer PLM 27,

was also sunk, taking an additional

12 sailors to their watery graves.

[Anthony Cantor] The SS Saganaga and the Lord Strathcona

were sunk by a German U-boat, resulting in an

additional 29 deaths and the loss of an enormous

amount of vital iron ore.

I guess the Germans figured that

if they could disrupt the iron ore supply chain,

it would interfere with the Allies' ability

to produce the machinery of war.

Thankfully, they were only successful in the short term.

[narrator] The four shipwrecks at the bottom of Conception Bay

are a somber reminder of the sacrifices made

in the name of combating tyranny.

And for the residents of Belle Island,

ghostly relics of a once-thriving mining industry

are now relegated to the fading memory of history.

Deep in the heart of the Western Pacific Ocean,

a group of 607 islands and islets

comprises the federated state of Micronesia.

On the western side lie the Yap Islands,

a small archipelago that's surrounded by coral reefs,

turquoise waters, and thick mangroves.

The Yap Archipelago is barely over 45 square miles,

and it's made up of four separate islands.

The largest one is also named Yap.

- The Yapese people have lived here for over 3,000 years.

It's a calm, tropical paradise with no more than

12,000 residents.

Camouflaged in the shadows of thick jungle leaves

stands a massive human-sized rock.

From a distance, you might think it's just a large boulder,

but up close, this rock shape is entirely unnatural.

It's all rounded and flat like a disc,

and there's even a hole through the middle.

And it's not the only one.

There are dozens of these things ranging from a few inches

to over 10 feet tall.

All their edges are smoothed out like they've been polished,

but a lot of them are cloaked with moss and lichen,

so they've been here for a long time.

What are these things?

[narrator] More than 7,000 miles away from the

Micronesian island of Yap, similar rocks found in the

Peak District National Park of central England

may hold the key to unraveling the stone disc mystery.

♪ ♪

On the grassy slopes of the park

are strange clusters of huge, rounded stones

that look a lot like the stones found on Yap Island.

These stones are also disc-shaped

with holes in the center.

Most of them are similar in size,

with the largest one measuring 7.2 feet in diameter

and weighing over 3 1/2 tons.

- They're known as the Peak District millstones.

Millstones are large rock discs usually used in pairs to grind

grains for food production.

In England, these millstones are an integral part

of the local cultural heritage.

The rise and fall of medieval milling

was critical for the history of agriculture.

[narrator] Starting from the 13th century,

stonemasons came to take advantage

of the region's abundant gritstone,

a special type of sandstone.

The Peak District millstones were even shipped

thousands of miles away to parts of Europe and America,

and it's estimated that there are still 1,500 millstones

scattered throughout the park.

- Millstones have been used for millennia by farmers

to grind grains like wheat or corn into flour.

It's entirely possible that Yap Islanders

could have developed similar tools

to crush or process local products

like betel nuts or dried coconut meat.

So could the stone discs found on Yap be millstones too?

The Peak District millstones are relatively uniform in size,

but the stones found on Yap Island vary drastically.

While the larger Yap Island stone discs

weigh thousands of pounds, the lighter ones only

weigh about 30 ounces.

They couldn't grind anything,

so they must be used for something else.

But what?

[narrator] Continuing to explore the island,

the botanist begins to see the strange stone

discs everywhere.

There are hundreds of them all over the islands.

[Sarah Klassen] It's extraordinary.

They are on the beaches, on the pathways,

and in the deep forest.

And wherever they are, they have an imposing presence,

denoting some kind of importance.

But for what?

The locations of these discs are not random.

A lot of them are placed right next to private homes

or neatly arranged on pathways leading to important sites,

like cultural gathering places.

So maybe these stones function as landmarks

or waypoints that help travelers navigate on the islands.

[narrator] Stone landmarks have been used throughout history

to guide people to their destinations.

In the Canadian Arctic, Inuit people stack

stones into shapes to communicate with each other.

They're called inukshuk.

In Inuktitut, it means "to act in the capacity of a human."

[James Ellis] But unlike inukshuk, the stone discs on

Yap Island have a pretty homogenous style,

regardless of their placement.

If they were used as landmarks to communicate important

information to the community, wouldn't there be different

shapes or combinations?

They're made from limestone.

Now, you might be thinking,

"That's not so weird. Limestone's really common."

Well, that is true in most places,

but it's not true on the Yap Islands.

There is no natural limestone on these islands at all.

Yap Island is composed mostly of rocks like schist and basalt.

So where did these stone discs come from?

[narrator] Approximately 300 miles southwest of Yap

is the archipelago of Palau, a group of islands

composed of a combination of volcanic material and limestone.

Inside one of the limestone caves....

There are three massive stone discs.

These are the same stones discovered on Yap.

The completed stone disc is almost 10 feet wide

and weighs an astonishing 8.4 metric tons.

[Sarah Klassen] This cave is a limestone quarry site

and the likely origin of many Yap stone discs.

Based on remnants and tools discovered at the site,

archaeologists conclude that the stones

were meticulously chiseled from the limestone base,

then polished and shaped before they were

transported to Yap.

These stones would be hard to transport,

even with modern means.

The holes carved into the centers of these stones

were integral to their transport and balance.

The Yapese inserted bamboo poles through those holes

to support their weight and then used wooden rollers

or bamboo scaffolding to move them into canoes

or onto bamboo rafts.

Given the size and the weight of these stones,

as well as the long distances from Palau to Yap,

and the great risk to the people involved,

the level of effort and dedication

that these Yap islanders poured into these circular rocks

is truly remarkable.

These discs must have been very valuable to the Yapese.

[narrator] According to Yapese oral tradition,

groups of courageous seafarers brought these beautiful stones

carved into the shape of a full moon to Yap.

They were deemed as the most prestigious item

to trade on the islands.

[Sarah Klassen] They're known to locals as Rai,

and they've been used as a version of currency

for centuries.

Today on Yap Island, there are sites where

the Rai are concentrated, referred to as money banks.

For the Yapese, the value of Rai

is not only determined by its size or craftsmanship,

but age and even the number of men

sacrificed on the voyage to get the stone to Yap.

When the value is settled, Rai can be used as a payment

for fishing equipment, animals, or even land.

[narrator] On the Yap Islands, the Rai stones serve

as a living memory that connects the Yapese

with their communities, other villages,

and the rich history of Micronesia.

Although modern money has replaced the stones

as everyday currency, the Rai stones are

still exchanged in traditional social transactions,

such as marriage, inheritance, or political deals.

They are another wonderful aspect

of this beautiful, jungle-cloaked,

wildlife-rich tropical paradise deep in the Pacific Ocean.