Original subtitles

[narrator] A breathtaking tower

in the forests of Croatia.

If this was in any town or city in the world,

it would make for an extraordinary landmark.

[narrator] Buildings in a Columbian ghost town

reclaimed by nature.

[Dougal] They've almost been sucked down

into the earth beneath them.

It's quite an eerie place.

[narrator] And a majestic facility

[narrator] And a majestic facility

on the banks of the Thames.

[Alicia] As you enter,

you can really feel the grandiosity of this place.

It's almost cathedral-like.

[narrator] Decaying relics, ruins of lost worlds,

sites haunted by the past,

their secrets waiting to be revealed.

[narrator] On the edge of New York Harbor is a colossal,

modern-looking building.

[Jim] This one, you can't miss, even from miles away,

you can see this structure is absolutely enormous.

It's quite a mystery what this is.

It has this big hangar-like feel.

You actually come to realize that there are two buildings

You actually come to realize that there are two buildings

that are linked by these huge hovering bridges.

[narrator] Only when entering inside

does its abandoned state become clear.

Its purpose, however, is anything but.

[Jim] In the center of the building

is this giant atrium

that goes up for several stories

and there is rail road tracks that run right through it.

[Geoff] But then it has these strange protuberances,

these balconies jutting out of the walls,

these balconies jutting out of the walls,

something like I've never seen before.

[narrator] This building was a response

to an unparalleled logistical challenge.

[Geoff] There's probably a few buildings in the world

that saw so many people come in and out of its doors.

And unfortunately,

who passed through the doors of this place

never came back alive.

[narrator] In 1917, the United States

entered the First World War,

entered the First World War,

but fighting on battlefields thousands of miles away

posed an unprecedented problem.

The US had a huge logistical challenge of

getting tens of thousands of troops

and thousands and thousands of tons of equipment,

food and supplies back and forth

across the Atlantic.

[narrator] An army of two million needed

to be raised and shipped across the ocean.

To overcome this mammoth task,

they designed this extraordinary complex.

they designed this extraordinary complex.

In so many areas,

this building is a record breaker,

and the reason for that is its incredibly innovative design.

[narrator] This is the Brooklyn Army Terminal,

and the man behind its creation is

renowned architect Cass Gilbert.

Now, Cass Gilbert is really well-known

for designing buildings like the neo-Gothic skyscraper,

the Woolworth Building.

This is obviously a very different building,

very utilitarian.

very utilitarian.

[narrator] Andrew Gustafson is an expert

on the history of the structure.

[Andrew] This building was built

entirely out of reinforced concrete.

And when it was built,

it was the largest concrete building in the world.

You can see, it was built with floors,

you know, almost 10 inches thick.

[Jim] The concrete structure was so robust,

they actually allowed the workers

to drive around in military jeeps.

And you can still see some of

the speed limit signs today.

[narrator] This was a vast logistical hub

that would carry urgently needed troops,

weapons and supplies to the trenches

of Western Europe,

and at its heart was the atrium.

[Andrew] This was designed to be the main cargo

handling area for the facility.

This was an indoor railyard.

You could drive two trains directly

into the building, and overhead,

it used to have glass so it could operate

24/7 year-round regardless of the weather.

24/7 year-round regardless of the weather.

These trains would pull in

and they would unload them onto this central platform.

And then above us,

we also have a pair of old 5-ton electric gantry cranes.

So these cranes could be positioned over that cargo,

they would lower a cable, pick it up,

and then they would drop it into these balconies.

[Geoff] It was really a marvel.

It had 96 centrally controlled freight elevators,

giving it just amazing logistical potential.

And it was the most advanced freight terminal

And it was the most advanced freight terminal

in the world at the time.

[narrator] The cargo wasn't just here to be stored.

It needed to be moved in and out

at a moment's notice.

For this, Cass Gilbert designed something unique.

So we're standing in the skybridge.

Essentially, they built a whole separate grade

on the third level that connected Warehouse A

out to the piers.

The idea was that once you loaded a piece of cargo

The idea was that once you loaded a piece of cargo

into the warehouse,

it never touched the ground again

until it was loaded onto a ship.

[Geoff] It meant that the Army Terminal

had the capability to do intermodal shipping.

There's no sort of barrier in between

where things have to be offloaded,

carried to the pier and then loaded again.

They'd come straight from the train and onto the ship,

vastly speeding up the process of supplying armies

or transporting troops.

[narrator] It was a groundbreaking site

built in record time.

built in record time.

This massive four million square foot facility of piers

and wharves and warehouses

and terminals was constructed over just 17 months,

four million square feet in 17 months.

[narrator] And yet, it wasn't quick enough.

The summer offensives of 1918, led by Britain and France,

had brought Germany to its knees.

By the fall, Allied victory was all but complete,

with 10,000 American troops arriving in France every day.

with 10,000 American troops arriving in France every day.

But not one of them came through this complex.

[Geoff] United States joined the war in April of 1917

but didn't get its first troops

into battle until June of 1918.

So we were planning on a 1919 campaign,

but the war ends in 1918.

So what do you do with this place?

[narrator] Completed in September 1919,

they had missed the war by 10 months,

they had missed the war by 10 months,

but it wasn't long before the government

found a new enemy of the state,

this time internally,

and it would give the terminal a new lease of life.

Prohibition starts in early 1920,

and all of a sudden the federal government

is mobilizing tons of resources

to fight the scourge of alcohol.

They confiscated an awful lot of liquor

in the city of New York.

A lot of it was stored here.

[Geoff] And at any given time during Prohibition,

there was something like a quarter of a billion dollars

in today's dollars' worth of confiscated drugs and alcohol

in these big buildings.

[Jim] In fact, at one point,

they had so much they started to dispose of it

through a hole in the dock.

[narrator] One New Yorker had a cunning plan

to exploit this situation.

That one day in 1927,

when they opened up that hole in the pier,

they discovered strings of about 20 buckets

they discovered strings of about 20 buckets

that were hanging on wires underneath that hole.

So someone had actually rowed underneath the pier,

strung up those buckets,

waited for them to dump out that slurry of beer and wine.

I don't know what they would advertise it as

but probably some pretty unpleasant stuff.

[narrator] The terminal proved a useful tool

in the fight against alcohol,

but its original wartime design was about

but its original wartime design was about

to be put to the test.

[narrator] This is the Brooklyn Army Terminal,

an epic construction designed to speed men

and materials across the Atlantic

during the First World War,

but the war was over before it was ready.

Soon, however, it would finally come into its own

and do what it was built for.

Most Americans had regarded to World War I

as the war to end all wars.

as the war to end all wars.

But then December 7, 1941,

the Japanese attack Pearl Harbor

and sink most of the American Pacific fleet.

America suddenly finds itself in a world war again.

With World War II,

you really have the Brooklyn Army Terminal

coming sort of full circle, so to speak,

to fulfill its original purpose.

The first two major deployments of the US Army

following the attack on Pearl Harbor,

both started right here.

On January 15, 1942, Operation Magnet began.

On January 15, 1942, Operation Magnet began.

And so this was a deployment of about 4,000

US Army troops going from Brooklyn to Belfast,

Northern Ireland,

to help reinforce the British there.

Just about a week after Operation Magnet,

we had another task force that was assembled

that was bringing the first American troops

into the Pacific theater.

Over the course of the war,

3.2 million military personnel moved through this building

3.2 million military personnel moved through this building

and 37 million tons of equipment.

[Geoff] The Brooklyn Army Terminal

became the largest supply base

anywhere in the world during World War II.

[narrator] The terminal also holds another sobering record.

It was the solemn duty and responsibility

of the Brooklyn Army terminal to actually

receive the remains of Americans killed

in the European theater.

In fact, 140,000 Americans came back

In fact, 140,000 Americans came back

to the Brooklyn Army Terminal.

That represents about three quarters

of all of the Americans

whose remains were repatriated to the United States.

[narrator] Although the Second World War

came to an end in 1945,

troop rotations continued through the Cold War.

And one of the more famous soldiers to depart

from the terminal was Elvis Presley.

[Michele] He's drafted into the military

and what he decides to do is rather

and what he decides to do is rather

than serve in special services,

which would have enabled him to perform

as a musician and entertain troops,

he actually decided to enlist as a regular soldier.

So he goes through basic training.

And in September of 1958,

he decides to hold this massive press scene

at Brooklyn Army Terminal before he departs.

This is a huge PR and marketing moment

for the US Army that this massive rock star

was putting his career on pause to serve his country.

was putting his career on pause to serve his country.

[narrator] Despite its once revolutionary design,

its days were numbered.

In 1966, it was forced out of business,

outdated by the advent of containerized shipping.

Yet its strength and design has ensured

that the Brooklyn Army Terminal still has a future.

[Jim] It's a sign of how well-made

and functional this building is that even though

and functional this building is that even though

much of it has sat empty for decades,

parts of it are now being reused

and new businesses are moving in,

restaurants, startup companies.

So some corners of this complex

are actually thriving with new life.

[narrator] In rural Colombia,

in the shadow of the Andes Mountains,

a site lies shattered and semi-hidden

in the undergrowth.

[Dougal] You've got sort of roads that sometimes

appear to lead nowhere or just disappear,

and then you've got buildings either side

that seem to have almost been engulfed by the ground.

[Alicia] Everything is really odd.

You don't know if the ground has risen up

or if the buildings have sunk down.

There's whole streets of buildings

that seem to be half missing, partly destroyed.

[Rob] The roofs have been removed off many

and the walls are caving in.

and the walls are caving in.

This isn't just the ravages of time that's done this.

[narrator] Whatever happened here

didn't just destroy the buildings.

[Rob] There are crosses,

gravestones and shrines everywhere.

[Alicia] Columbia has a really tumultuous

and dangerous history.

Was this war, was this violence

or was this something else?

[Dougal] And this is one of the worst disasters

of this kind in human history.

It's certainly up there as one of the most dramatic.

It's certainly up there as one of the most dramatic.

[narrator] This is the town of Armero.

When Freddy Gutierrez lived here,

it was a thriving community.

[Freddy speaking Spanish]

[translator] On our right, we have what was Carmen's church

and on our left, the stadium.

Over there in that corner,

there was a pretty big playground.

I always remember, the hustle and bustle.

I always remember, the hustle and bustle.

[narrator] At its height,

this town was home to around 30,000 residents.

Freddy lived here with his parents and two brothers.

[speaking Spanish]

[translator] This is the house on 21st Street.

We lived happily in that house.

We lived here until November 13.

From here, we left that night.

[narrator] Overnight, this town was transformed

from a place of life and vitality into a wasteland.

from a place of life and vitality into a wasteland.

And the reason lay 45 miles west.

[Alicia] We are in the plateaus

of Nevado Del Ruiz,

which completely dominates the landscape.

[Rob] Although the volcano had been silent for decades,

in 1984, all that started to change.

[Alicia] The first sign was tremors,

and then the following March, a UN

seismologist actually observed a 500 foot vapor column

seismologist actually observed a 500 foot vapor column

and determined that this was a precursor

to a massive eruption.

[Dougal] By October 1985,

a fairly detailed hazard map had been put together

and it was clear that they'd outlined a number of places

that should or needed to be evacuated.

[narrator] At the center of that map lay Armero,

and the damage would likely be catastrophic

due to the unique features of this volcano.

[Dougal] It's some 17,400 plus feet high,

[Dougal] It's some 17,400 plus feet high,

and even though it's near the equator,

because of its height,

its upper parts and its peak is covered in snow and ice.

If you impart hot volcanic material onto snow and ice,

you very quickly turn it into water

and you can mix that loose volcanic material into almost,

like, what we call a volcanic slurry.

And this phenomenon, called a lahar,

can be quite deadly.

[narrator] The hazard map placed Armero directly

in the firing line of these lahars.

in the firing line of these lahars.

But what the geologists predicted

and what the residents were told

were two very different things.

[Rob] The map met with criticism from the authorities

because they felt that it was too alarming

and so they decided not to widely distribute it

amongst the population.

[narrator] Armero's residents wouldn't be ready

for what was coming their way.

[Rob] The possibility of lahars was high,

and geologists predicted that any magma

coming through the summit

could have devastating effects.

could have devastating effects.

They desperately urged local officials to evacuate,

but it seems that their warnings fell on deaf ears.

[narrator] Six weeks after the hazard map

had been produced

and the evacuation of Armero first

recommended disaster struck.

On November 13, 1985,

black ash began to spew out of the volcano

and immediately geologists

demanded the evacuation of Armero

demanded the evacuation of Armero

and the neighboring villages.

[narrator] Despite this, Radio Armero called

for residents not to panic and stay in their homes,

a message echoed by the town's priest

over the church's loudspeakers.

Just after 9:00 p.m., the volcano blew.

With a massive storm and lashing rain outside,

few heard the warning signs.

As predicted, the eruption produced pyroclastic flows

As predicted, the eruption produced pyroclastic flows

that melted the summer glaciers and snow,

creating four thick lahars.

But these were far worse than anyone

could have ever imagined.

[Freddy speaking Spanish]

[translator] When the avalanche hit the town,

I would say the first symptom was the horrific sound of it.

It was indescribable.

[narrator] Freddy's parents didn't hang around.

They grabbed the three children,

left the house and headed down the street,

left the house and headed down the street,

ash falling in the darkness.

[translator] We were all very scared because

you know something is coming after you to hurt you.

But we knew nothing else. We didn't know what to do.

[narrator] Lahars cascaded into the west side of town,

but Freddy was a mile from the initial impact

and they pushed north towards the church.

[Freddy speaking Spanish]

[translator] Unfortunately, as we were approaching the church,

we realized the avalanche was

we realized the avalanche was

coming down towards the stadium.

We were grabbing trees, walls, anything.

But a second avalanche came

and raised the mud level again.

That was the moment we found ourselves

with the mud up to our necks.

[Rob] Within minutes,

85% of the town was covered in mud and debris.

The sheer volume and speed of the mudflows was astounding.

[Freddy speaking Spanish]

[translator] My younger brother slipped away from my mom's arms.

[translator] My younger brother slipped away from my mom's arms.

She managed to save him.

And when she took him from the mud,

he was completely naked.

He had just turned three years old.

[narrator] Many were swept away or pulled under

and suffocated by the thick mud of the lahars.

[Freddy speaking Spanish]

[translator] The level was rising and getting thicker, too.

We had to cling to the trees as a group to stay together.

[narrator] Soon, they heard a familiar voice.

[narrator] Soon, they heard a familiar voice.

It was a local taking refuge on a nearby roof,

and he helped them climb the trees to safety.

[Freddy speaking Spanish]

[translator] It was the most tragic night.

We prayed for our lives, for everyone's lives,

and for the town, which was in that moment disappearing.

[narrator] Huddled together,

they prepared to see out the night.

No idea what scene awaited them in the morning.

[narrator] In October 1985,

geologists produced a hazard map

that placed the town of Armero in imminent danger

from one of Colombia's largest volcanoes.

But authorities downplayed the danger,

leaving residents totally unprepared for the mudslides

known as lahars that ravaged the town.

[speaking Spanish]

[translator] The horror, the uncertainty

[translator] The horror, the uncertainty

about more avalanches coming,

a deep silence covering everything,

just before people who got stuck started to shout

and cry and not knowing

what was beneath us or if we could sink.

[narrator] Freddy and his family survived the night

on a rooftop as everything around them

was consumed by mud.

They were rescued the next day,

but after a disastrous relief operation,

but after a disastrous relief operation,

around 23,000 people were believed to have died.

Many of their bodies never found.

It has been the deadliest lahar in recorded history.

[Dougal] It erupted some 35 million tons of material,

but that's only about 3% to 4% of

what came out of the famous

Mount St. Helens eruption in 1980.

So in many ways,

it was a relatively small explosive volcanic event.

But if you couple that with the hot material

landing on snow and ice,

landing on snow and ice,

when you then funnel that power down the river valleys,

you can turn something that's a relatively

small eruption into a deadly lahar.

[narrator] The town's buildings

most destroyed or buried,

some still visible but half sunken,

are testament to its power.

It serves as a stark warning

that ignoring advice of scientists

is a dangerous game.

The town, never rebuilt,

is preserved as a memorial to the dead.

is preserved as a memorial to the dead.

For those left behind,

the events of that night are always with them.

[Freddy speaking Spanish]

[translator] Our mourning continues for our city,

for all the people who died and for all that was lost.

However, we have to find our place

in the world and move forward.

[narrator] On the banks of the River Thames,

12 miles east of Central London

12 miles east of Central London

is a diamond in the rough.

[Sascha] This location is far from appealing,

and I speak as a fan of the city of London,

this site is not easy on the eye.

[narrator] But inside is a building

very much at odds with its setting.

[Sascha] You have this magnificent arched doorway,

[Sascha] You have this magnificent arched doorway,

but you'd never imagine what lays beyond that doorway.

It's a complete contrast to the really industrial nature

of the surrounding area.

The first time you walk into this building,

it's like walking into one of the great cathedrals.

It really does have a feeling of

grandiosity about it.

All those ornate ironwork interiors with vivid,

bright colors.

[narrator] The site played a vital role in the growth of

[narrator] The site played a vital role in the growth of

what was the largest city in the world.

This wasn't just a well-designed complex,

it also housed a public health solution.

[Sascha] This is really one of the most magnificent

feats of Victorian engineering,

and yet most people,

even though it's right under their feet,

have never seen it and know that much about it.

[Peter] One day in 1989, I got a strange phone call,

[Peter] One day in 1989, I got a strange phone call,

it turned out from a small group of

retired engineers and they said,

"We're trying to restore one of your

great-great-grandfather's places,

come and have a look."

[narrator] Peter Bazalgette arrived

at a decrepit facility left abandoned for decades.

[Peter] When I first came into this mysterious place,

it hadn't been properly used since the Second World War,

it was rusting away, full of dead pigeons.

I was over-awed by the grandeur of it,

I was over-awed by the grandeur of it,

but sadly, it was a decaying grandeur.

[narrator] Neglected in this industrial wasteland,

Peter joined forces with a team of retired engineers

and set about saving this forgotten piece of heritage.

[Peter] When I was a kid in the 1950s and '60s,

I knew I had a very famous relative

from the Victorian age.

Nobody else did.

We didn't value what the Victorians

had done for us.

That's very different today.

[narrator] Designed by his great-great grandfather,

[narrator] Designed by his great-great grandfather,

Sir Joseph Bazalgette,

and still boasting the biggest rotative-beam engines

in the world,

it was the product of a health crisis

in mid-19th century London.

In London's poor east side,

construction and sanitation were completely unregulated,

and London became known as a city of two halves,

with the wealthy being able to afford

to escape to the cleaner air of West London.

In the poor half,

you had a dense population crammed together

in tiny houses with rats

in tiny houses with rats

and sewage running between them

down the narrow cobbled streets.

[Sascha] You didn't have clean running water.

You had houses that were infested with vermin

and people living just cheek to jowl,

crowded with one another in very,

very unhealthy conditions.

These were the Victorian slums.

[narrator] But soon enough,

even those in the West couldn't escape

the smell of human excrement.

the smell of human excrement.

The long, hot summer of 1858

caused a horrendous stench to emanate

from London's mighty river.

[narrator] It was known as the Great Stink.

[Dominic] The smell began wafting

into buildings everywhere,

including the houses of Parliament.

And because they still believed in the miasma theory

that disease was spread by air or bad smells,

they all thought their own health was at serious risk.

[narrator] Cholera had been ravaging

London's population for decades.

London's population for decades.

Sewage pumped directly into the river

was spreading the disease, but through the water supply,

not through the air, as they believed.

Cholera is a highly infectious disease

that is spread through water

that has been contaminated by fecal matter.

[narrator] Physician John Snow

had made the connection years earlier

and understood this was a water borne disease.

But even by 1858, few accepted his findings.

But even by 1858, few accepted his findings.

[Alicia] These politicians literally believed

that they were inhaling diseases.

So that was really the last straw to get them to act

and to commission Bazalgette to begin his project.

[narrator] Bazalgette's task was to clean up the city

and prevent the spread of disease.

[Alicia] Joseph Bazalgette was the chief engineer

of the Metropolitan Board of Works

and his first job in this relatively new organization

was to fix London's sewage problem.

was to fix London's sewage problem.

And his plan was to run main sewers

from the West of the city to the East,

and those sewers would run parallel to the Thames

but keep the sewage out of the Thames.

[Dominic] The whole system consisted of 1,300 miles

and 82 miles of West-East intercepting sewers.

For seven years,

Joseph Bazalgette dug up the whole of London.

Joseph Bazalgette dug up the whole of London.

He had to cross railway lines, he had to cross canals,

he had to redesign the center of London.

I imagine everybody in those days

was cursing Joseph Bazalgette for disrupting London,

but not after 1865,

when it was all finished and London was cleansed.

Because his sewage system was trailblazing.

It was an innovation.

It showed how a modern city could work.

[narrator] But how did this building fit

into that revolutionary system?

[narrator] In response to the Great Stink of 1858,

Sir Joseph Bazalgette was tasked with cleaning up

London's Thames River by revolutionizing

the city's sewage system.

He devised and had built a network of sewers

that carried the city's wastewater to two vast pumping

and filtration systems, either side of the Thames,

and filtration systems, either side of the Thames,

just east of the metropolitan conurbation.

[narrator] One of those was the pumping station

here at Crossness.

Well, this flywheel belongs to a rotative steam-beam engine.

In fact, there are four in this building,

the four largest ever built ever in the world.

And they're named after the members

of the British Royal Family, Queen Victoria,

Prince Albert, Alexandra, one of their daughters,

and Bertie, one of their sons.

[Dominic] The four massive engines at Crossness

pumped sewage into a reservoir that held 25 million gallons.

The sewage was then released with the ebb tide,

so it flowed safely out to sea.

[narrator] The opening ceremony in 1865

was held at Crossness with great pomp.

[Sascha] The pumping station became

known as the Cathedral of Sewage

and in a fashion typical of ceremonies

and in a fashion typical of ceremonies

in the capital of imperial Britain,

it was opened with a grand ceremony,

possibly the most lavish meal ever served

inside a sewage facility.

Just look at this,

some of the finest Victorian wrought-ironwork

ever commissioned.

And it shows one thing about the Victorians,

immensely proud of public works,

this was a building essentially

for pumping excrement.

for pumping excrement.

[narrator] For 80 years,

the beam engines at Crossness turned.

But after the Second World War,

more advanced engines rendered them redundant.

But thanks to a group of enthusiasts,

Crossness would find a new lease of life.

[Alicia] With all of the colors

and intricate metal design,

it's clear that a lot of work went

into this restoration project.

[Sascha] The trust decided to intervene

and restore part of the building

and restore part of the building

and also to restore one of the engines,

and now it can be seen operating

in all its former glory.

[Peter] Thirty years after I first walked in here,

and thanks to the extraordinary efforts

of the members of The Crossness Engines Trust,

we now have a living museum, a living steam museum.

[Peter] And if you look at this magnificent beam arm

of this restored engine, look at the way it's painted,

look at the majesty of it.

look at the majesty of it.

You can tell that today we really appreciate

what the Victorians did and how they really created

modern society that we still rely on today.

[narrator] While this pumping station has been restored,

parts of Bazalgette's system never went out of use.

So they're building a new super sewer,

not to replace but to complement Joseph's system.

[Sascha] That the intercepting sewers

[Sascha] That the intercepting sewers

are still in use 150 years later,

it's really a testament to the overall

build quality of the system

as it was originally constructed.

[narrator] 60 miles south of Zagreb,

in the wooded hills of Petrova Gora,

a dazzling building sits high on a mountain peak.

[Rob] The building almost swallows you whole.

[Rob] The building almost swallows you whole.

It's simply otherworldly.

[Michele] It looks modern.

It makes you think of something

that would be in a city.

But this is in the mountains, in the middle of nowhere.

[narrator] As you venture in,

you realize it is just as modern and abstract inside.

[Lynette] This is something that you merge into

as you would come into a place of worship.

[Rob] Although there aren't any windows,

it's surprisingly light inside.

it's surprisingly light inside.

The offset slices allow streams of light

to flood in from above.

[Michele] It's not some abandoned industrial works,

but it's on an industrial scale almost.

It's just this really perplexing building

that looks out of place.

[Rob] These vast concrete curves

covered in stainless steel,

spiraling up a 120 feet into the sky

make for an extraordinary landmark.

make for an extraordinary landmark.

[narrator] But what was its purpose

and why has such a striking landmark

seemingly been left to ruin?

[narrator] Cedomir Studen is a local historian

and custodian of this remarkable complex.

[Cedomir speaking Croatian]

[translator] As you can see from the configuration of the building,

this was a very ambitious and futuristic project.

There are 11 floors in total.

There are 11 floors in total.

Downstairs, under the ground, there is a concert hall,

which can host up to 1,000 people.

On the floors above were educational

and exhibition spaces,

and it did all that with multimedia tools,

which made it a trailblazer of its kind.

[narrator] The reason for its existence

can be unearthed from the woods it overlooks.

[Rob] This huge towering building

[Rob] This huge towering building

dominates the hillside,

but it's not the only structure here.

When you start exploring,

you come across some more abandoned buildings

very deep in the woods.

These buildings are scattered about,

and when you go inside,

it's clear that people once lived here.

[narrator] Those that filled these empty cabins

were engaged in a desperate fight for survival,

part of an ethnic conflict that dates

back to the interwar period.

back to the interwar period.

Between the First and Second World Wars,

there was constant fighting

amongst the various ethnic groups

that comprised Yugoslavia.

[narrator] At the forefront of the power struggle

were the right wing fascist group, the Ustasa.

[Lynette] The Croatian Ustasa believed that Croats

were ethnically superior to especially Serbs.

[Michele] Many Croat nationalists

[Michele] Many Croat nationalists

supported the Ustasa

because they believed that this was a ticket

to independence from Serbia.

[narrator] When the Nazis invaded Yugoslavia

in April 1941, the Ustasa were natural allies.

The Nazis were very happy to contribute

to the disintegration of the Kingdom of Yugoslavia

and to take the Croatian part

and turn it into a puppet state

and turn it into a puppet state

that was ruled by the Ustasa.

[narrator] This fascist alliance

wouldn't go unchallenged.

But how does the striking tower

on the hill fit into this story?

[narrator] In the shadow of a conspicuous landmark

are the remains of a partisan stronghold

buried in the woods,

set up to fight the Nazi-backed Ustasa.

[Cedomir speaking Croatian]

[translator] We are now arriving at a place

which played an extremely important role in the history

of the resistance during the Second World War.

[narrator] Those behind it

[narrator] Those behind it

were the Kordun Partisan Detachment,

part of the People's Liberation Army of Yugoslavia,

and at the helm was one of history's

most notorious leaders.

It was led by a figure who would become a major player

in 20th century politics, Josip Broz,

who was also known as Tito.

He's a communist and envisions a Yugoslavia

that is going to share that political ideology.

[narrator] To overthrow the Ustasa,

[narrator] To overthrow the Ustasa,

Tito needed an army

and secure bases to operate from.

[Cedomir speaking Croatian]

[translator] We are at the Central Partisan Hospital complex.

There was the surgery, there were hospital wards,

a dental surgery, a kitchen.

Up there was the watchtower.

These buildings provided an entire infrastructure.

[narrator] Using guerrilla tactics,

they ambushed the Ustasa from their bases deep in the woods,

they ambushed the Ustasa from their bases deep in the woods,

while recruiting more Serbs to join their cause.

[Cedomir speaking Croatian]

[translator] In this region of Petrova Gora,

there were 15 active detachments.

The Kordun Partisan Detachments

were mainly made up of local villagers.

[narrator] For the partisans to survive,

it was essential their stronghold remained hidden.

[Cedomir speaking Croatian]

[translator] Here is an example,

a field lavatory that looks like a toilet

a field lavatory that looks like a toilet

but can be speedily dismantled,

opened up and entered into

and used to hide wounded soldiers inside.

[narrator] This 30-building strong hospital

masked a network of underground bunkers

capable of sheltering hundreds of soldiers.

It wasn't long, though,

before the Ustasa had the stronghold of

Petrova Gora firmly in their sights.

Petrova Gora firmly in their sights.

In early April 1942,

there was a sudden breakthrough of defenses.

The Ustasa forces stormed multiple

partisan positions around Petrova Gora.

Given that these ethnic Serbs only had

crude weapons and pitchforks,

given that they were going against armed soldiers,

they really stood no chance.

[Cedomir speaking Croatian]

[translator] The cruel revenge of the Ustasa regime

resulted in one-third of

resulted in one-third of

Kordun's residents getting killed,

98% of whom were Serbs.

[narrator] The Ustasa continued

their vicious attempts

to cleanse the region of Serbs,

yet this hospital was never discovered.

And as the tide of war turned against the Nazis, Tito,

backed by the British and his communist allies,

emerged victorious.

Tito's prestige as the man

who led the opposition to the Nazis

who led the opposition to the Nazis

and to the Ustasa made him a national hero across

what was Yugoslavia.

[narrator] Under Tito's firm grip,

Yugoslavia was brought back together,

and for many years there was relative peace

between the ethnic groups.

This structure was built as a symbolic phoenix

rising from the ashes of war.

[Cedomir speaking Croatian]

[translator] Tito was in favor of erecting

a memorial in this place

a memorial in this place

because he wanted to express his gratitude

to the local people for their sacrifice during the war.

[Rob] The stainless steel panels

are hugely reflective,

and this effect symbolizes light overcoming darkness.

Within the structure was originally a museum,

which housed hundreds of documents,

relics and artifacts related to the battle

and the history of the ethnic Serbians'

and the history of the ethnic Serbians'

struggles in the region.

[narrator] But just before it opened in 1981,

Tito died and with him the peace he had brought.

Ethnic divisions resurfaced, and in 1991, war erupted.

With the onset of the Yugoslav Wars,

the monument falls into disrepair,

it's looted, it is defaced.

So it has a really sad ending.

[narrator] Today, Yugoslavia is a distant memory,

but the monument that still stands here

tells a story that must not be forgotten.

[Cedomir speaking Croatian]

[translator] This devastated monument

represents a particular significance

of this place in the hearts of the local population.

It reminds us of a time when people fought against those

who had lost their humanity.