Original subtitles

A high-tech industrial site now lost to dense forest.

Without that production, Hitler's war machine

would simply grind to a halt.

A giant chimney stack that became a towering inferno over Baltimore.

It's really, really sturdy, almost over-built walls, because they

were afraid of a collapse from wind or some other natural disaster.

An abandoned tower consumed by a bizarre force of nature.

It's a very strange picture, because what was there before

is no longer there now.

And a mysterious installation that waged a cold war in Berlin.

It was so brazen, it must have been a giant middle finger to the ussr.

Once they were some of

the most advanced structures and facilities on the planet,

at the cutting edge of design and construction.

Today, they stand abandoned, contaminated and sometimes deadly.

But who built them, and how and why were they abandoned?

♪ ♪

On the baltic coast of Poland, near the village of police,

is a 450 acre fenced off area of forest.

Smashed concrete structures litter this overgrown site.

Skeletal buildings riddled

with collapsing walls, underground shelters and a network of tunnels.

Hidden under the trees in northern Poland is this labyrinth of

concrete structures.

It's quite clearly something that was industrial.

That kind of thing does not

happen overnight, and not without a vast investment of time and money.

A group of mangled structures

are clustered together at the heart of the forest,

flanked by the pulverized remains of tower blocks

and a strange brick coloured tower that soars over the trees.

When you look closely, there are clues to tell you exactly

what happened there.

On the side of one building is marked in German 'coal bunker 4'

and then not far away, there's the remains of what was, quite

obviously, large storage tanks and right there, those two elements

are the core of the story that tells you what happened there.

What was the purpose of this site?

What events took place here and why was it abandoned?

In the 1930s, the town of police was part of Nazi Germany,

and would play a major role in Adolf Hitler's plans for war.

Germany had already been rearming in secret for years,

when Hitler openly announced his policy of rearmament in 1935.

Hitler, however, faced a critical obstacle

to building up his military forces.

Very few people know that Germany really lacked the natural resources

required to fight a major war.

Apart from coal and water, at the time, pretty much everything

else was imported, and that

critical lack played a huge role in Hitler's preparations for war.

One crippling energy shortage

outweighed all others, and that was fuel.

Without it, not a single aircraft could fly, ship sail

or tank roll across the battlefield.

The Germans suffered from real constraints in all of their

operations from fuel.

Through world war ii, the prime mover,

the main transport was the m1a1 horse, pulling a wagon.

Germany had almost no fuel, and was therefore heavily

reliant on imports.

In the drive to become self-sufficient,

they set out to create their own.

The modern equivalent of almost 1 billion pounds

was spent on this site - the politz synthetic oil plant.

In 1937, construction started on the huge industrial complex.

This was no ordinary refinery,

but rather a state-of-the-art facility that used a revolutionary

new process called hydrogenation to turn Germany's coal into oil.

The Germans

used methods to make fuel out of coal that were developed in

the early 20th century on to the mid 20th century.

They produce beautiful fuels, but they produce fuel

that is very, very pure but mindbogglingly expensive.

The synthetic fuel

is created by liquifying powdered coal.

In a reactor, a mixture of heavy oil, hydrogen

gas and a catalyst is heated to almost 400 degrees celsius,

and subjected to the incredible pressure of 10,000 pounds

per square inch.

This dangerous process made politz a lethal environment for its thousands

of slave labourers.

The economics of it really don't add up.

It's said that it takes 6 tonnes of coal to produce 1 tonne of

synthetic oil and that's before you consider the amount of coal

it takes to ship everything around.

And whilst, for Hitler, that may have served a purpose of Nazi

Germany, in any other economy that just won't fly.

After four years of construction, politz finally began fuel production

in 1941.

At the heart of the plant was the coal mill.

Packed around it were numerous storage tanks, distillation plants,

pressure chambers and hundreds of miles of piping,

needed to carry the vital fuel to waiting trains and tankers offshore.

Politz had gone into production just in time to help fuel the 3,000 tanks

and 2,500 aircraft that took part in operation barbarossa,

Hitler's colossal attack on the Soviet union.

By 1943, the plant was producing

a staggering 7,000 tonnes - 15% of all Germany's fuel.

The synthetic fuel plants kept Germany in the war.

That was Germany's only reliable

source of fuel and so they were quite dependent on those plants.

Without that production coming out from politz, Hitler's war machine

would simply grind to a halt.

Whilst pivotal to Hitler's war machine, it came at a terrible cost.

30,000 slave labourers were brought in from across occupied Europe

and the Soviet union to operate the complex and dangerous machinery.

Nearly half of these prisoners died from the brutal treatment and toxic

working conditions at the plant.

13,000 slave labourers gave their lives at politz alone,

and that's something that should never be forgotten.

As allied forces gradually gained the upper hand, synthetic

fuel from plants like politz became ever more vital for Hitler's armies.

The Germans are really dependent upon these synthetic fuel plants,

and when those plants are attacked, then there will be a huge drop off

in the capability, for example there is no fuel to train pilots.

They're producing air planes but

there's no fuel and it will become progressively worse.

The critical weakness of synthetic oil was now exposed.

It relied on coal to make it, but coal was desperately needed by

other industries - power stations and even the trains and ships that

were taking the oil away from politz itself.

There simply wasn't enough fuel to go around.

The German war effort

has got to expend a lot more resource on burning 1l of high

test aviation gas than the British or the Americans or the Russians.

The Germans are fighting a much more expensive war, because they

haven't got key resources.

By late 1944, politz was within reach of allied bomber fleets

operating from britain and Italy.

And in January, 1945, they unleashed a devastating 14-minute air raid.

More than 1,600 bombs pulverised the plant.

This hammer blow mortally wounded the German war machine.

Once the campaign gets going,

you see a dramatic drop in German oil reserves,

and in the supplies available for the German army, and this impacts

the German operational effectiveness quite severely.

By February 1945, the red army was closing in.

The chemists and engineers running operations fled west for safety,

and after the war, the Soviet union looted the remaining equipment,

leaving the ruins of politz abandoned.

Today, the remains of this once high-tech refinery are accessible

and can be explored with care.

They are a forgotten monument to oil production, the achilles' heel

of Hitler's third reich.

The allies pulled out

all the stops to try and bring production to an end, and if you

visit politz today, there's evidence of that everywhere.

Huge craters in the ground, roofs, all these building destroyed,

some buildings completely turned over.

The devastation there was phenomenal, because it was

so important for the allies.

That was their means of bringing Nazi Germany to an end.

Politz reminds us of the horror of death, it reminds us of mass

enslavement under cover of war, and it reminds us of the Nazi idea

that cruelty and enslavement

could create fuel where there was none.

Over 4,000 miles away in the heart of Baltimore, Maryland,

looms an incredible yet largely unknown structure.

Hemmed in by office blocks, this tower is from a bygone era

and is, to many of the city's inhabitants, an enigma.

So, if I was just randomly driving through the middle of Baltimore

and I saw this massive brick structure in front of me,

I think I'd be pretty confused to be honest, because I would think,

"is it a chimney for a factory, is it part of a power plant,

is it even for storage?"

It was the tallest structure in the United States.

Not only was it made of brick, but it was made of so many bricks.

The tower reaches a height of 215 feet.

Pierced only by a few

deep set windows, it soars high above the surrounding streets.

At the base of the tower is an iron door

that leads through the 4.5 feet thick wall, and into a hollow shaft.

Jackson gilman-forlini is an historic properties coordinator

and works for the preservation of the city's historic buildings.

It is quite a climb.

I mean going 215 feet, you know, it's over 13, 14 stories high.

It really is an engineering masterpiece and this really

was untrodden ground.

Wooden beams rise up out of sight, supporting bizarre zig-zag

shaped iron brackets.

Around the walls, a creaking staircase leads to the summit.

The smooth surface of the tower's

interior is testament to the skilled workmanship

in laying the kiln fired Clay bricks.

The intricate wooden framework lining it reveals the complex

engineering that went into its construction.

But what was the purpose of this mighty building and why

was it abandoned?

Decades after the war of independence,

the American military was again in conflict with Great Britain.

During the war of 1812, when the British set fire to the white

house, the American military were still reliant on imported ammunition

from France, Holland and Spain.

Unable to manufacture the huge quantities of ammunition

they needed, it was a crucial weakness in their defences.

The United States, at this time this was built, was still

a relatively young country, that was trying to come onto

its own on the world stage, and therefore, it needed a way of

producing military armaments quickly and inexpensively.

In 1828, Charles carroll III, a surviving signatory of the us

declaration of independence, laid the foundation stone for this,

the Phoenix shot tower.

This vertical factory made lead musket balls

and round bullets called shot.

It was designed to produce 100,000 bags

of shot every year, each bag weighing 25 pounds.

To construct this impressive building, it required the production

of well over a million bricks.

This presented a potential problem.

The limitation of the structure

was probably due to the compressive strength of the brick at

the bottom, right, you can only make it so high before the weight

of the structure above just crushes the bricks at the bottom.

Despite this, the extraordinary new building began to take shape.

Yard after yard, it reached farther into the sky.

The need for such height lay in the science.

The time when the shot tower was constructed,

guns would shoot spherical, basically, lead projectiles

out of 'em, and the most efficient way to do that is to

pour molten lead from a height, which, as it falls, the molten

lead coalesces into a sphere, almost like a perfect sphere.

The process was invented by William watts of Bristol in 1782,

the same year he built the first ever shot tower.

The technique relied on an ingenious use of physics to

achieve the perfectly round bullet.

Tonnes of lead were hauled to the top of the tower

and heated to nearly 330 degrees celsius to create molten lead.

This was then poured through a copper sieve.

The combination of surface tension and friction with the air

turned the folding drops of molten lead into perfect spheres

before they hit a cooling pool of water at the bottom of the tower.

You're basically using gravity,

you're using physics, to create a sphere, so it makes perfect sense.

But clearly what you need for that is a lot of height,

and how do you get height? It's by building a massive brick tower.

Building a 215 foot tower presented major challenges.

They didn't really know entirely what they were

getting themselves into.

Incredibly, no scaffolding was used to build this, it was built

entirely one level at a time, slowly building bricks

as they went up.

It's really, really sturdy, almost over-built walls, because they were

afraid of a collapse from wind or some other natural disaster,

and so, this tower is really strong

as a rock, because of those super thick, load bearing masonry walls.

But with no scaffolding,

the tower's sheer height made working conditions

extremely dangerous.

This led to the introduction of one of its most distinctive features.

That cast iron

metal track, it looks kind of strange and a lot

of people ask what it is but it's actually a early braking

system for a kind of elevator. They didn't just put

any old elevator in, they thought about, "well, what

happens if a rope actually snaps?"

There was a terrible accident in which workers fell to

the bottom, but thankfully survived.

After that, they installed this track so that the box for

the pulley system had spokes, which would fit into the track.

So if there was a breakage, it would very slowly kind of

shift its way down to the bottom of the tower and hopefully no-one

would get hurt.

Just a year after the first brick was laid, the Phoenix

tower went into production in 1829.

Probably one of the most effective ways that the United States had of

making shot, it was a huge production facility that created

hundreds of thousands of bags of shot.

For over 30 years, the Phoenix shot tower successfully produced

spherical bullets for muskets.

Then, on the Eve of the American civil war, more advanced rifle

ammunition was developed.

New, conical-shaped bullets that spun on exit,

offered greater range and accuracy.

This contributed to the staggering casualty rates seen

on the battlefields of america in the 1860s.

The shot tower no longer had a role

to play in america's military production.

So, the tower created bullets for

the nation's civilian game hunters instead.

Yet production was brought to a dramatic halt in September 1878,

when the wooden interior caught fire.

The flames were shooting out so much that the fire itself

could be seen from miles away.

The fire burnt out all of the internal structure of the shot

tower, but the bricks itself remained intact, due to their

inherent resistance to fire.

Well, brick is actually a really good insulator. What that means

is it doesn't get very hot or very cold very easily, and because of

the thickness of the brick it actually contained the fire.

The heat just couldn't penetrate through this massive wall of Clay,

and, also, remember that this Clay has actually been fired to much

higher temperatures already than the fire would have been producing.

The tower Rose from the flames like a Phoenix.

Just a month after the fire, it reopened for business.

Towards the late 1800s, more efficient methods

for making round lead bullets resulted in the tower's demise.

Hauling tonnes of led up a high

tower was increasingly seen as too hazardous and inefficient.

The Phoenix tower closed its iron doors for good in 1892.

Today, the Phoenix shot tower stands as a monument to a bygone era.

It helped de-shackle the American military

from its reliance on foreign-made ammunition.

Yet, without a concerted effort, this abandoned vertical factory

would have vanished without trace.

The tower had been purchased by a gas and oil company,

which did propose tearing the tower down.

However, the citizenry of Baltimore loved it so much and cherished it

as a landmark, that they rallied together and raised

the money to purchase the tower and then donated it to the city

government for safe keeping.

Now open as a museum, the Phoenix shot tower

is more than just a symbol of outdated technology.

Not only did this incredible brick factory help to revolutionise

the production of ammunition, it was also a vital stepping stone

towards the nation's world-leading military industries.

Across the Atlantic ocean, in western Berlin,

a battered shell of a building looks over a tree-covered hill.

This hill is called the teufelsberg, or devil's mountain.

The name adds a sinister touch

to the strange structure rising out of the trees.

At first sight all you're thinking is, "I don't know what this is,

but it's an eye-sore."

It looks almost like an ancient prussian castle,

then suddenly it turns into a bizarre modern facility,

strangely perched on a peak,

overlooking the modern city of Berlin.

Towering 260 feet above

the surrounding plateau is a central tower topped by a mysterious dome.

Two more tattered domes

flank the tower, and nearby, another one rises from the summit.

Ragged plastic sheeting exposes their ruined interior.

Surrounding them is a sprawling complex of derelict facilities.

This thing is really a hangout for rebels, conspiracy theorists,

counterculture intellectuals, and most definitely graffiti

artists, and there's a sort of an angry presence to it.

Mystery surrounds this strange ruin.

What was its original purpose and why was it abandoned?

In the 1960s, Berlin was at the centre of cold war espionage.

The city was divided into four sectors, three run by the allies -

america, britain and France.

While the eastern side was under Soviet control.

Democratic west Berlin was surrounded and enveloped by

communist east Germany,

making west Berlin easy prey for the Soviet union's network of spies.

The American embassy in Moscow is riddled with listening equipment.

The American fleet at sea is constantly being tailed

by Soviet fishing trawlers bristling with listening equipment.

Everybody is shadowing everybody.

Though encircled, america's national security agency, the NSA,

took advantage of their close proximity to communist Berlin.

They built a cutting-edge listening station

called field station Berlin,

known to its operators simply as 'the hill'.

We had listening posts with large antennas all around

the periphery of the Soviet union, collecting electronic intelligence,

and it was especially well placed, because it's 150 miles inside

the enemy lines in this enclave of west Berlin.

Teufelsberg was a place where we in the west could listen in and get a

look inside the operations of the Soviet armed forces.

In 1963, a year after the Cuban missile crisis brought the world

to the brink of nuclear war,

engineers began constructing the new monitoring station

on the summit of devil's mountain.

The foundations of the new complex were dug deep into the ground,

but not into standard bedrock.

Devil's mountain is actually 13 million cubic yards of rubble -

a mound created with the war time ruins of Nazi Berlin.

Beneath this devil's hill is something really interesting,

a Nazi technical college, designed and constructed by Albert speer,

and it was designed so well they couldn't knock it down,

so they just buried it.

As soon as the hill went into operation, the Soviet union were

desperate to shut it down, in large part because its

surveillance technology was proving highly effective.

In each of the distinctive domes was an antenna, a rotating

parabolic radio antenna that intercepted Soviet communications.

Monitoring this radio chatter gave the NSA valuable insight

into military manoeuvres behind the iron curtain.

However, to maintain the shape of the plastic sheeting over the main

dome, the whole structure had to be kept under pressure with potentially

life threatening consequences.

It's interesting that the iconic ray domes are still there today.

Now, these were thin plastic put over frames in a highly

pressurised room, and we're told, interestingly, that

the men who worked there had to go through a decompression chamber

upon leaving, or otherwise risk getting decompression sickness.

The Soviets continuously attempted to block or interfere with us army

radio communications.

This was a practice known as jamming.

Now, jamming was a standard procedure of the Soviet union,

but in this case, there's not a lot you can do

with an enclave that's deep inside

your system, without jamming your own radio transmissions.

This structure, high up on the hill,

it was so brazen, it must've been a giant middle finger to the ussr.

Year after year, the hill listening station gathered intelligence on

the strength and capabilities of Soviet and east German forces,

and nuclear missile launch units were given top priority.

You can learn a lot from military operations

from just listening, even if you haven't broken their codes.

We understood that

when we were on the radio, the other guys were listening,

and they understood that as well.

Both sides continuously eavesdropped

on their opponent's radio communications.

But for more than 30 years, the hill's location in Berlin, right

at the heart of communist Germany, gave the west a crucial advantage.

You're surrounded by a large number of Soviet east German divisions,

which are holding manoeuvres, which are pushing the radio traffic,

and it's a great place to listen to all of their patter, their tactical

operational transmissions.

The Soviets failed in their quest.

They never managed to put an end to the NSA's surveillance.

However, with the collapse of the Soviet union

and the Warsaw pact in 1989, the cold war came to an end.

The hill became redundant,

and as soon as it was decommissioned, it was stripped

of its secret monitoring equipment.

All that remained was an empty shell.

Today, the teufelsberg listening station is a ruin, overlooking

the united city of Berlin, yet it's rebellious status remains intact.

Who wants to remember that paranoia, that imminent

destruction?

So, now it's a graffiti gallery and maybe that's appropriate,

you know, maybe that's even healing.

Even today, details of its

surveillance work are classified, but the knowledge and experience

gained on this mountain of Nazi rubble gave the us and its allies

a lead in signals intelligence that has never been lost.

We're looking at people's bandwidths and transmissions

all the time, and it's still a very,

very big part of intelligence, in fact, it's probably a bigger

part of intelligence today than it was before.

The site has now has been completely stripped of all its equipment,

so there's no clue about what it actually found,

and, to this day it remains highly classified, in fact, top secret.

430 miles away, on the northern tip of Denmark, a solitary ruin

stands in total isolation.

The derelict tower

overlooks the sea from its position on top of a huge sand dune.

When you think of shifting sand dunes, you possibly conjure up

images of the Sahara and vast desert landscapes.

You certainly don't automatically think of Denmark.

Perched precariously on this desolate landscape, it overlooks

the skagerrak, the narrow strait of water that separates Denmark,

Norway and Sweden.

When you see this tower emerging out of the sand,

I mean it's eerie, it's mysterious.

It's a very strange initial picture, and that's primarily

because what was there before is no longer there now.

The 75 foot masonry tower is topped by a glass-fronted turret.

Scattered around its base are the remains

of buildings submerged in the sand.

The whole structure is precariously balanced

on the lip of a sheer sand cliff, 200 feet above the crashing waves.

What really stands out, as it rises up

into the sky and looms over the cliffs, is when it was built,

the tower was strong enough to withstand even the strongest Gale.

So why was this one abandoned?

In both world wars, this stretch of water, the skagerrak strait,

was the German Navy's main gateway to the open ocean.

This tower witnessed prowling British submarines lying in wait,

and the 'Bismarck' sailing to its doom.

But centuries earlier, the Danish government had realised

its critical importance to trade.

To become a global power, they need to help ships navigate

one of the most dangerous stretches of water in the northern hemisphere.

Jacob kofoed is a guide and curator at this unique site.

It were very dangerous to sail at this sea.

There was a lot of storm from the west and boats often come into

trouble, so they want to make some lighthouses

along the coastline.

With a budget equivalent to nearly 750,000 pounds in today's money,

the Danish lights and buoys service

commissioned a revolutionary lighthouse.

They called it the rubjerg knude fyr.

In march 1899,

construction began on a complex of buildings on a 200 foot high cliff.

For safety, it was set 200 yards back from the shoreline.

From its clifftop position, the light should be visible

across miles of sea and save countless lives.

Now, ships still frequently sail through these waters, and in stormy

and foggy conditions, even with the advent of modern technology,

lighthouses are still needed

for captains to know where the land starts.

After nearly two years of construction,

in late 1900,

the light at the top of the white tower was finally switched on.

It was powered by a 550 watt bulb

and had state-of-the-art French-made fresnel lenses to

amplify the beam.

With numerous glass rings stacked at

different angles, the fresnel lens focused light towards its centre.

On clear days, this allowed it to be seen from 25 miles away.

However, sand picked up by strong winds along the coast

constantly clogged its machinery and scarred the fresnel glass.

And engineers hadn't foreseen an even bigger problem.

When it was built, rubjerg knude was 200 yards inland and 200 ft

above sea level, and miles away to

the south was a sand dune, but not just any sand dune.

The rubjerg mile is the largest moving sand dune in Northern Europe.

For 300 years, 5 million cubic yards of sand crept

along Denmark's northern coast at a dramatic rate of 60 feet a year.

It's really hard to imagine that a country like Denmark

could have a slow-moving sand Tsunami creeping up the coast.

The sand dunes themselves always have a sort of back slope,

a windward slope, and then a slip face where the sand gets

blown up, it bounces up and falls down the slip face, and slowly,

through time, it migrates across the land's surface.

We can't stop the wind, so we're not gonna be able

to stop the sand dunes that are migrating because of the wind.

The fact is, this sand dune had been moving for centuries,

but where the lighthouse was built, there was never any reason to think

that the sand would ever be any kind of threat.

For over 20 years, the tower's light and foghorn penetrated

darkness and mist to keep vessels clear of the dangerous shallows.

By the 1920s, however, the rubjerg mile dune

had arrived on its doorstep, to the horror of engineers.

They tried to just do a kind of king canute and stop the sand in

its tracks. They put barriers in the way to stop the sand migrating.

On doing so, there was a big traffic jam of sand building up

and the dune got bigger and bigger.

So, actually, then you've created a bigger problem,

'cause you've created a bigger dune.

In an unlikely twist, the 200 foot cliff that made

the lighthouse so visible, now acted as a ramp and carried

the slow moving Tsunami of sand up and over the lighthouse complex.

The sand had made its way all the way up that cliff,

and had swallowed up the buildings around rubjard knude.

The sand was laying around the lighthouse

and the big dunes were built up there, and higher and higher.

Though the sands have now shifted position,

in 1953, the dune actually grew higher than the lighthouse itself.

Trapped in a hollow in the sand, the light and fog signal

were no longer clear to ships at sea.

The only way they figured they could save the lighthouse was by

continuously digging away the sand around the base,

but even then they must have known this was a battle against nature

they were never going to win.

In 1968, authorities finally gave up the battle

against the flood of sand, and the light was decommissioned.

Yet the tower itself and its surviving buildings became a museum

and study centre for sand dune movement.

Ironically, though the peak of the massive dune had long moved on,

the museum itself was slowly crushed by the sand and closed in 2002,

when the whole site was finally abandoned.

Today, the lighthouse at rubjard knude is an empty shell.

Every year thousands of visitors

climb the mountain of sand to explore its haunting remains.

The onshore winds that suffocated the light with sand

have also scoured away the cliff on which it stands.

The coastline is coming too close and closer,

so in a few years, maybe two,

three, four, five, six years, there's no lighthouse any longer.

The rolling dunes may have snuffed out the light,

but in the very near future, erosion will cause the mighty

tower to collapse into the waves.

The engineers who built

the lighthouse believed its location and solid construction

could withstand anything the elements could throw at it.

But they didn't anticipate

the extraordinary power of the wind to transform the landscape itself.

There's always a need to take into account your natural surroundings,

but mother nature has a way of continuously reminding you

who's really in charge.

Now abandoned,

they were once on the cutting-edge of human engineering.

Within these decaying structures are the echoes of history,

they speak of war and terror,

but also of exploration and human endeavour.

Captioned by ai-media ai-media. TV