All language subtitles for Abandoned.Engineering.S08E07.The.Secret.Bunker.1080p.WEB-DL.AAC2.0.H.264-squalor_track3_[eng]

Narrator: A marooned structure
in america with an infested past.

In every direction you
see nothing but ocean,

this place is truly far out

but the importance of this
site cannot be underestimated.

The brutalist palace once
home to a Bulgarian dictator.

When it was completed,
the ruler of the country

decided he liked it so much,

he was going to
keep it all for himself.

An Australian island where
criminals created a safe harbour.

This place which was designed
to house the worst of the worst,

ended up being a vital part
of Australia's response to war.

And the colossal wartime project

the Nazis thought
no one knew about.

The British did
something very smart,

they let the Germans
keep working on it.

Decaying relics...

..Ruins of lost worlds...

..Sites haunted by the past.

Their secrets waiting
to be revealed.

Far off the southern
tip of Florida usa,

is a ruin lost at sea.

So most people think that
key west itself is remote,

but this place, this is even
further remote than that.

Though this is
technically part of the us,

it feels like you've
dropped off a map.

Cast adrift on a small island,

its appearance on the horizon
comes as a surprise to most.

This place is really a mystery

because it's this huge pile
of brick and mortar masonry

in the middle of
the Gulf of Mexico.

When you first see this place
as it rises up out of the ocean,

you can't help but feel amazed
and in awe but a little spooked.

It's weathered the
storms of decades

or perhaps centuries
but still standing strong.

Distinctive features betray
some of the sites secrets

but others remain hidden.

This place looks like a
fort but that's not all it was.

This was not somewhere
you wanted to end up.

For some of the people
who were sent to this island,

it would become a
deadly, deadly place.

This vast abandoned structure
emerges from the ocean,

more than 100 miles
beyond the Florida peninsula.

Adam Hollywood has been
making regular trips out here

for almost 20 years.

And knows the lay of
the land better than most.

This is the end of a
barrier reef system

that runs all the way from Miami
out here to the middle of the Gulf.

It creates the choke point
for the entire Gulf of Mexico,

so any large ships,

they would have to
sail to the south of us

and then up in to
the Gulf of Mexico.

When this place was built,
the primary concern was piracy.

The United States was
interested in protecting shipping

along the American
coast and in the Caribbean,

and so this provided
a strategic location

to police these waters.

Piracy may have been the
motivation for building here

but pirates weren't
the only threat.

Ever since the war of 1812
when the British laid siege

to the city of New Orleans

and threatened to cut off all trade
exiting the Mississippi river delta,

the Gulf of Mexico became
a strategically vital place

for the new United
States of America,

so it would make sense
that they would build a fort

in the Gulf of Mexico

to basically assert
American power in this region.

This is fort Jefferson,

construction began here in 1846

and initially slaves
were forced to carry out

much of the heavy lifting.

But details across the site show
that change was on the horizon.

This place is
absolutely enormous

but if you look closer,

you can also see
some irregularities,

some of the bricks
are different colours.

In 1861, the American
civil war broke out,

remaining in union hands,

this island became a
potentially decisive position

from which to
blockade the south.

If they could get the
fort completed in time.

First two tiers are made up of
a light tan or Sandy colour brick

and all those bricks are
coming from pensacola Florida.

But when Florida
joined the confederacy,

they stopped sending
bricks from Florida,

so then we had to start
getting bricks from rural Maine,

so when you look at
the third tier of this fort,

you'll see the bricks are much
darker redder looking bricks.

And they weren't waiting until
the right shade came about,

they were interested in completing
this job as quickly as possible.

Following the
emancipation proclamation,

the union needed to
find a new workforce.

The site's location made a
choice of whom to employ easy.

Another thing with this
island that was really important

was its isolation and that
made it ideal for a prison.

In this case union deserters
would be sent down there,

Lincoln would have them form
a really crucial body of workers

who would do all sorts
of tasks on the island.

Although the fort was still
not technically complete,

soon enough was built
to make it ready for war.

From this fort here, fort Jefferson
as well as fort Zachery Taylor

in key west,

the ships that worked
out of these harbours

were able to capture over
300 shiploads of supplies

that were going to the south.

While fort Jefferson left
its Mark on the civil war,

one prisoner would leave his
own imprint on the forts history.

Samuel mudd was the
most famous prisoner

we had here in the dry
Tortugas at fort Jefferson,

he was convicted of
being a co-conspirator

in the assassination
of President Lincoln.

On 14 April 1865, in the
final days of the civil war...

..President Abraham Lincoln
attended a performance at a theatre

near the white house.

While he's watching the show
an assassin enters his box,

shoots him in the
head from behind

and then to escape,
leaps out of Lincoln's box,

catches his boot in some
bunting coming down,

breaks his leg.

Whilst on the run,

the assassin John wilkes booth

stops at the house of dr
Samuel mudd who set his leg.

Mudd however fails
to alert the authorities.

Two days later, suspicions
of mudd's complicity

in the assassination were raised

and it proved enough
for a conviction.

Samuel mudd himself, he was
sent here to the dry Tortugas

at fort Jefferson to do
a lifetime of hard labour.

Mudd quickly learned
this would be no easy ride.

Tourists pay good money to
come to places like this nowadays

because of the beaches,
'cause of the sea, the sun

but nobody wanted
to go to fort Jefferson

during the American civil war,

it was, it was basically a
one way ticket to death.

Finding even the basic human
necessities was a struggle.

One of the absolute challenges
in a site such as this one

would be the
matter of freshwater.

Evidence in the cells

show the lengths the
inmates would go to for water.

They actually dug trenches
out in the cement floor

and then bowls that
would help store the water.

And so you can see even today,

we had a little bit
of rain last night

and these trenches help
fill up these bowls of water.

So these would just
help give the prisoners

enough freshwater to survive.

A large desalination
system was installed

to provide a steady
supply of drinking water.

But storing this
water in barrels

would inadvertently have
deadly consequences.

Something happens that is going
to drastically change things for mudd

in prison,

it's going to completely
change the trajectory

of his experience there.

On 18 August 1867,
a prisoner became ill

and within a short time
over 30 people would fall ill

on one single night.

Fort Jefferson had been hit
by an outbreak of yellow fever.

This incredibly
violent, horrible disease

that could make
people so deathly ill,

it causes a yellowing
of the skin, jaundicing,

that's why it's yellow fever.

Before long, the fort's doctor
succumbed to the disease,

suddenly responsibility
for the sick fell to dr mudd.

It's believed that he utilised
the forts design to aid his efforts.

Yellow fever is a viral disease
that is spread by mosquitos.

Their collection of water
that they had desalinated

had actually been a
breeding ground for mosquitos

and so that was really
the heart of the problem.

This hallway was
actually designed

to help create a breeze
to vent out the smoke

and the heat from the cannons
that would have been in these rooms.

One of the things that
Samuel mudd did realise is that

bringing people up on
to the second level of fort

seemed to reduce the number
of people that were getting sick

here at the fort.

The fact is mosquitos, they
tend to stay low to the ground,

they don't fly into
a lot of strong wind.

Alongside this, mudd introduced
far stricter hygiene procedures

when dealing with the
patients and it worked,

mudd's efforts saved many lives.

From his heroic efforts,

mudd was granted
clemency and he was freed,

he went home on an
appropriately named ship,

the Liberty.

Once home, mudd resumed
his own medical practice

where he worked
until his death in 1883.

Fort Jefferson itself
was never completed.

And by 1874 in a
rapidly changing world,

it was abandoned.

Today the fort and
surrounding areas

are under the authority of
the national park service.

It's a wildlife refuge that
not only enables people

to enjoy the nature

but also to have an appreciation

of an unexpected history
in an unexpected place.

In Bulgaria,

a sprawling complex
hides in the foothills

of the lyulin mountains.

The area is very famous
for mineral Springs

where people would
go to recuperate.

It was a place for relaxation
for important people,

for people of means.

Traces of luxury
litter this place.

The architecture, it's a mixture
between stark and ornate,

it's got this kind of
grandiosity of the place.

This is strange when you
consider the country's past,

in recent years,

it wasn't a place
known for its wealth.

This extravagant resort
is conspicuous in design.

Yet there are no signs to it
and it's buried deep in the woods.

Why build something this
showy and then hide it?

Architect iliyan nikolov,

worked on the
construction of this building,

he hasn't been back
here for 40 years.

Iliyan worked here in
1978, his father, pavel,

designed this place.

The costly finish on its
now crumbling facade

suggests that this building
was designed to be special.

The story of this
dilapidated place

dates back to the
aftermath of world war ii.

When Bulgaria fell
under the influence

of Stalin's Soviet union.

By 1954,

the communist leader, todor
zhivkov had taken charge.

Todor zhivkov was
trusted by Stalin

and by subsequent Soviet rulers

because he was a yes man.

Zhivkov's loyalty
meant that by the 1970s,

he was still in power

and he gave his approval
for construction at this site

in 1973.

It was intended as a
holiday spa complex

where hard-working party
members could come and recuperate

in the regions healing waters.

It's now known as
bankya residence.

Iliyan remembers
its grand design.

But construction here
was shrouded in secrecy.

The egalitarian
communist state of Bulgaria

is hiding away something
for the privileged

in a state where nobody
was supposed to be privileged.

The work was done
in complete secrecy

because the government
didn't want anybody to know

about the hypocrisy that
coursed through every aspect of it.

After this complex
was completed in 1977,

zhivkov liked it so much,

he decided that even Bulgaria's
elite would not be given access.

This place was meant
to be for the many

but one man decided
to keep it for himself.

For decades, zhivkov
kept bankya residence

as his unofficial
private country house

but his behaviour was
earning him many enemies.

When zhivkov himself wasn't
a particularly nice character,

he was very quick to
eliminate any potential threats.

Everyone in his
country hated him,

if they had the chance
they'd have got rid of him.

As zhivkov's paranoia grew,

his secret police became
increasingly aggressive.

And even those beyond
Bulgaria's borders were not safe.

In 1978, Georgie markov a
BBC world services correspondent

and a Bulgarian dissident was
murdered on Waterloo bridge

by a Bulgarian assassin

using an umbrella
with a poisoned tip.

And dilapidated structures
at the edge of the compound

show how far zhivkov would
go to ensure his safety here.

Zhivkov wanted to beef
up the security for himself

and the people around him

and so he set up extra
accommodation for his secret police.

Unbeknown, even
to the architects,

zhivkov added a secret tunnel
that connected the buildings.

However, his real protection was
ensured by his Soviet overlords

and his close personal friendship
with their leader, leonid brezhnev.

Addicted to
tranquilisers and alcohol,

brezhnev had serious
health problems,

so in 1979, zhivkov bought
him here to the bankya residence.

Zhivkov invited him

to come to this sort of
cleansing mountain retreat

and he wanted to
kind of curry favour

with his kind of
Russian masters.

Inside the retreat, brezhnev
wallowed in the luxury.

The expertly designed
pool took advantage

of all the regions beauty.

The pool itself

was full of bankya's famed
healing mineral water.

But personal tragedy
soon left todor zhivkov

more cut off than ever.

With the death of his
beloved daughter, lyudmila,

in 1981,

zhivkov withdrew to the
secluded bankya residence.

He took up almost permanent
residence at the site,

and remove himself
away from that tragedy.

And he rules Bulgaria

from his little
hideaway out in the hills.

He is seen less and less

and Bulgaria is less
and less well ruled.

The next year the death
of his ally, leonid brezhnev,

followed by the
softening of communism

meant zhivkov's
days were numbered.

He was finally ousted in
a bloodless coup in 1989.

He was actually kicked
out of the residence and

then he was held up for
trial for embezzling money.

Zhivkov was convicted,

confined to house
arrest and died in 1998.

Meanwhile, the life of his
beloved bankya residence

had taken a bizarre turn.

A Japanese billionairess bought
it to convert it into a golf club,

she repainted the site
pink and lived there herself.

The billionaire died in 1999

and after a brief spell
as an upmarket brothel,

the bankya residence
was abandoned.

Iliyan's father was
never given credit

for his unique
architectural work.

And iliyan now hopes
to reverse the fortunes

of bankya residence.

In northern Germany, on
the banks of the river visa

sits a mammoth building.

It's a vast expanse of cement

that is just plonked
down in the countryside.

It doesn't have any
indications on the outside

of what its function would be.

There is not really any windows,

there's only a couple of
openings in the whole building.

And it's cavernous interior
seems carefully engineered

to support the Titanic roof.

The struts and the
columns that hold up

this very heavy roof are
clearly perfectly designed.

Massively manufactured
from concrete and steel,

clearly, it housed
something very important.

Out of the gloom, a
distinct order emerges.

It's organised in to a
series of enormous bays

with big thick concrete
walls between them

and as you work your way
to the last couple of bays,

you can see that
they've got water in them.

So who built these watery tombs

and shrouded them in thick
concrete and why did they do it?

Dr Marcus meyer is the
scientific director here.

We know from the age and
from its overall military look

that it was something
built during world war ii.

By 1943, Germany was
struggling to maintain its foothold

in world war ii.

The writing was really on the
wall for the Nazis at this point,

it was only a matter of time

before their reich collapsed
under military pressure,

from the Russians in the east,

the allies in the
south and the west.

Germany is being bombed

from the British
isles, from Italy

and is being strangled
by an economic blockade.

This precision building

hints at how Germany
planned to fight back.

The location might be a clue,

it's right next to a major waterway
that flows into the north sea.

What do you want to put here
that needs access to the ocean?

With the allies
dominating the skies,

the Germans needed to
regain control of the Atlantic.

The most effective naval weapon

that Germany has is the
u-boat, the German submarine.

The German u-boat sunk
something like 3,000 allied ships,

they thought if they
could build enough u-boats

to go out and sink as much
allied shipping as possible,

then maybe they could
negotiate some kinds of terms

that would be
advantageous to them.

The type 21 u-boat is
what they have in mind.

This is going to be a
diesel-electric submarine

that can keep
Germany in the war.

You can't just
build it in a shipyard

because the aerial
bombing campaign

which is pulverising all the
German manufacturing facilities,

so this place has got to be able
to withstand a huge bombing raid.

The result is this,

the German's top-secret
u-boat manufacturing facility,

codenamed bunker Valentin,

it's located far from the coast
away from the allies prying eyes.

Secrecy was Paramount

and it was no mean
feat to keep construction

of this enormous
bunker under wraps.

The Nazi's greatest challenge
was how to build a bomb-proof roof.

They built large arches
to hold up the roof,

those are built on site

but then later lifted
in to place with cranes

and then more concrete
was poured on top of that.

By the time they were done,
the roof was at least 15 feet thick.

But the Nazis knew this
wouldn't be thick enough

to stand up to the ally's bombs.

So they ordered some sections
to be increased to 23 feet.

This vast piece of engineering
came at a tragic human cost.

This building was essentially
constructed with slave labour,

it's believed they used
10,000 to 12,000 prisoners

to work on this project.

The conditions were
absolutely brutal.

It's not known how
many sacrificed their lives

to bring this secret
facility to near completion

in less than years.

This was conceived
as a really fast-paced

assembly line for submarines.

The different submarine
components would arrive by rail

and by barge

and then they'd essentially
be bolted together in this facility.

The plan was that at each bay,

more of a submarine
would be assembled

then passed along
the system of rails.

In total, each
submarine was intended

to pass through 12 bays

until finally, it was ready
to enter the lock chamber.

By 1945, the
submarine assembly line

was on the brink of building
it's first state of the art u-boat.

But unbeknown to German
intelligence, the British were watching.

The British had no
intention of attacking

until the moment was right.

They let the Germans
keep working on it,

keep pouring man, and material,
and time, and money and effort

into this huge project

and the British knew
the minute it was done,

they knew exactly
what was going on.

On 27 march 1945,

20 Lancaster bombers
of britain's 617 squadron

known as the dambusters,

flew undetected
towards bunker Valentin.

Loaded with grand
slam and tallboy bombs.

They knew exactly how to
target the most vulnerable section

of the bunkers roof.

They penetrate the
thinner section, the west end

and then they get into the
guts of the thing, blasting it apart.

Their timing was perfect.

The British did
something very smart,

they could have bombed this
project while it was being constructed

but they didn't.

Though bunker Valentin
remains standing,

the damage was done.

Nazi Germany didn't have
the time or resources to rebuild

and overnight, their
hope of victory was gone.

And this enormous structure

never even began
producing submarines.

After the war was over,

bunker Valentin had one
more onslaught to face.

In march of 1946, the
British and Americans

decide that, "hey, this
Valentin submarine bunker,

"it's the, a perfect place to
test bunker-buster bombs."

They fly a number of missions

dropping everything
in their inventory

and amazingly, this
Valentin submarine bunker

withstands even this
barrage of aerial bombs.

The colossal bunker has been
slowly crumbling ever since.

In Australia, in the
middle of Sydney harbour

sits a tiny island.

It's cluttered with
rusting cranes,

old industrial-looking
warehouses and washed up boats.

An incongruous
villa stands alone.

And beyond that sits
an imposing structure.

There are these big
windows and the airy rooms

but there's something else.

There are bars on the
windows, tiny cells inside,

clearly most of the people
here were not here by choice.

The building is covered in
spikes and hand-carved scratches.

Clues as to who built
the industrial structures

that crowd this place.

There's what looks
like a huge warehouse

with a turbine inside

and there's a sign on it
and it reads, "Scotland."

Below ground, there's more.

An eerie tunnel runs
for almost 200 yards

right through the
belly of the island.

What was this built for?

Polly nowicki has spent seven
years exploring this island,

which was first inhabited

by Australia's
indigenous eora people.

They called this place wareamah

and it was a special
sacred place for women

to travel in canoes here

and it was a place of
childbirth, for privacy.

But when the British
arrived in the 18th century,

they changed this place
from a cradle of birth

to something far more deadly
and they gave it a new name.

The name makes it sounds
like quite a chirpy chipper place,

however it was anything but.

Renamed cockatoo island,

it was perfect for what
the British had in mind.

Britain and especially
London had a crime problem

but they didn't have
enough prisons either.

Their solution was clear,
Australia, the great southern land.

In 1788, the area that
we now know as Sydney

was opened up as a
penile colony for the British

but it quickly
became overcrowded

and this is where cockatoo
island comes into the picture.

The first convicts to arrive
here in 1839 faced a brutal task.

The convicts
excavated tonnes of rock

to construct their
own prison buildings.

Each convict was
assigned a signature,

they would use a small
chisel to carve out this shape,

you can see the x's,

the lines and the
different kind of shapes,

so each signature meant
that they were assigned

a different amount
of bricks to build.

They built themselves a
grisly punishment block.

So this is solitary confinement,

where they would keep
prisoners for up to 12 days

with only half a pound of bread.

The abandoned jail reveals
the appalling living conditions.

On the windows, you can see
that men have actually grabbed up

to try and get a
breath of fresh air

and we have a diary entry
from reverend John pendrill

and he describes
walking up the road here

saying that he could
see up to 20 faces

pressed up against the bars,

just trying to get a
breathe of fresh air.

Only one prisoner
ever managed to escape

with the help of his wife who
was over on the mainland.

She rides the horse there,

she climbs down
the edge of the cliff

and she swims
to cockatoo island,

it's about a 20-minute swim,

there's bull sharks,
strong currents,

all sorts of things in her way,

on top of her supposedly
being pregnant.

She gave him what he
needed to cut his shackles

and he manages to swim
to the other side to freedom.

Once the prisons
construction was completed,

the inmates were set to task on
an even more formidable challenge.

One that would only further
the might of their oppressors.

During the 19th century,

European nations became
much more interested

in expanding their empires in
south east Asia and the pacific.

Britain needed a place
in this part of the world

where they could repair
and maintain ships.

It was decided that cockatoo
island, with its deep-water

and abundant supply
of convict labour

would be the ideal location.

They started work
on a dockyard in 1847.

This is fitzroy dock,

it was constructed
by convict labour.

It was pretty tough work,
the stones are quite large

and they had to carve it away
with a small kind of pitch hammer.

Their assignment was
digging three feet a day

into the bare rock.

An estimated 1.5 million
cubic feet of rock was excavated

and it was only
supposed to take 470 days

but it ended up taking years
due to the unruliness and unrest

of the poorly treated
convict workforce.

By 30 September 1857, the
dock was finally ready to use.

Without water,
it's about 4m deep,

it's not as deep as it looks but
it is quite wide and quite long.

But there was a problem,

there was no power on cockatoo
island and nowhere to build the generator.

To transform the basic stone dock
in to a modern naval powerhouse,

chief engineer, gother kerr mann,
was forced to take drastic measures.

Marks on a sandstone cliff
face reveal what happened next.

There's these lines of
sort of dynamite ridges

where he's dropped
that dynamite down

and he blew out
that side of the island.

He was changing
the shape of the island

to make way for this
huge turbine haul.

In one of the biggest
structures on cockatoo island,

cutting edge technology
gave fitzroy dock the capacity

to build and repair
modern warships.

Inside the turbine hall,
this is one of our iron giants,

it came from Scotland in parts

and it is actually
a huge scale lathe

and it's used for sort
of carving out metal.

And to enhance the
scope of their prized facility,

the British commissioned
another even bigger dock.

Naval technology
doesn't stand still

and as sail ships gave
way to steamships,

the dock had to be changed

to accommodate these
newer larger vessels.

So now, the convicts
had to carve out this,

sutherland dock,

it was the biggest single
dry dock in the world.

It included five enormous
hand-hewn slipways

where ships were launched.

These are two of our
slipways on cockatoo island,

this was a very busy place at
the height of these launchings,

it was very popular.

The addition of a
tunnel to move workers

and machinery underground,

made cockatoo island
the leading naval facility

in the south pacific.

This place which was designed
to house the worst of the worst

ended up being a vital part
of Australia's response to war.

Throughout the first
half of the 20th century,

it was put to the test.

After docking nearly 2,000
ships during world war I,

cockatoo island would play
a vital role in the next one.

After Japan entered
world war ii in 1941,

the stage was set for
naval warfare in the pacific.

Submarines came in for repair,

warships docked here, this
place was a hive of activity.

And when the American
warship USS New Orleans

was bombed by the Japanese in
1942, she retreated to cockatoo island.

Although the dockyards were able
to make the ship fighting fit again,

the real damage had been done.

This is where it
came, so in 1942,

they would dockside here
up to 60 lead-lined coffins

to send back to america.

After the war, shipbuilding
and repair declined.

The last ship to be constructed
on the island was hmas success,

which launched in 1984,

it was the largest naval vessel
ever to be built in Australia.

Finally in 1991,

the cockatoo island
dockyards closed down.

Today, this treasure
trove of maritime industry

needs preserving.

We're constantly working
on trying to rehabilitate

all the old machines
on the island,

that's interesting,
innovative and fascinating.

And the forced labour of
the cockatoo island convicts

will not be forgotten.

Sometimes places
created out of unfreedom

serve a vital purpose in
protecting freedom and democracy.

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