Original subtitles

The towering remains of a mountainside structure

built to withstand a colossal force.

What is it? What happened to it? What caused it to explode?

A sprawling cityscape that's been deserted and left to the elements.

It's like a giant been brought to its knees. But by what?

Strange military platforms that

harbour secrets of an underwater war.

Suddenly 200m from us.

Du, du, du, du.

We were really like "oh, what is this?"

And a heavy-weight structure in the eastern European countryside.

You'd be very confused if you came across it, this

almost alien structure plopped down in the middle of the woods.

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?

♪ ♪

In Europe, high up in the mountainous region

of the central Italian alps stands a large cathedral-like structure.

Towering 140ft above

the valley floor, this structure looks almost alien in the landscape.

It's like a fortress

from 'lord of the rings' that's been brought to life.

The eerie grey concrete alongside the windswept mountains

makes you shiver inside.

This huge structure set in this glorious natural setting,

there's mountains, there's lakes.

As you move round the side of it you look and go

"uh oh, what happened here?"

If it were complete it would stretch from one side of the valley

right across to the other.

But there's a massive gap in the middle.

Years ago, the central section of this great wall was ripped out.

Was it bombed? Was it an earthquake?

This would have been an event that caused a whole lot of disruption

and death.

How could something that appeared so solid

have failed so spectacularly?

So, what happened? And is new evidence changing our understanding

of its calamitous demise?

The story began in the unstable years before the first world war

when Italy was struggling to catch up with Europe's major

industrial powers.

Progress, such as it was, was mainly focussed in

the north of the country.

While the south was still blighted by severe economic stagnation.

As a result, many working class Italians moved to big cities such as

turin and Milan which quickly became overpopulated and overcrowded.

What was more between the year 1900 and the beginning of the first world

war, some 9 million, mainly southern Italians, migrated to

the usa in search of a better life.

Meanwhile, to speed the growth of new factories

wealthy capitalists invested in hydroelectric power stations in

the mountainous region of the alps.

These are the remains of one of those projects,

the gleno dam.

But it was built in troubled times, when anarchists were occupying

factories and some were even planting bombs at targeted sites.

Italy in the north was a place of great political unrest.

You had the capitalist who were effectively under siege from

a communist movement that had a whole different direction and mind.

Turmoil and violence, those were a day-to-day occurrence.

The man who financed the project was from the vigano family,

a family of wealthy industrialists from Milan.

Vigano constantly criticised

the local workers that he did employ.

His preference was to use milanese

workers instead of local workers which caused a lot of bad feeling.

If the people that are trying to put this structure together

are not working together

in unison, then you are gonna get a problem in the actual end product.

Building began in 1917

when the first world war was in full flow.

But a few years into construction soaring costs saw drastic design

changes and the vigano family decide to cut corners by using cheaper

lower grade materials.

Construction of the dam used poor quality concrete,

reinforced with first world war anti grenade netting,

neither of which were appropriate for this kind of structure.

Whenever any of those workers complained about those materials,

they were immediately fired.

Foundations are critical to all structures.

If you start to put in scrap metals, you don't really know

what the composition of those metals are.

They may have rusted and so then when you're pouring

concrete around that, you might not get a very good bind

between the metal and the concrete and that is really, really

important to maintain the strength of the structure.

So, was it a disaster waiting to happen?

In October 1923, with the dam finally built,

the reservoir was filled to capacity for the first time.

But problems had already begun to arise.

In the Autumn of the year there was an extremely heavy rainfall

and this caused some minor leaks in the dam that should have served

as a warning but in fact they were regarded as

"mm, that's not a problem." As the downpours continued,

the water levels soon crept above the maximum permitted depth

testing the dam's structural capacity to the very limit.

By the 1st of December, it seemed to have reached breaking point.

It was just another day when the caretaker was carrying out

his routine checks on the dam. And then he felt a tremor.

45 minutes later, the whole dam burst.

According to news reports at the time

there was a violent blast of air.

Then water rushed down into the valley below.

Over a billion gallons of water suddenly forced its way through

the breach at a speed of 70km/h.

A tragedy was inevitable.

The water would have been like a giant tidal wave, a Tsunami,

with debris just rushing through

the valley below causing devastation wherever it went.

The flood wave took about 45 minutes to crash

its way along down the valley.

The flood destroyed three villages, five power stations and countless

numbers of isolated buildings and factories along the valley.

By the time waters settled, over 350 people had been killed.

The vigano family and the dam's engineers were blamed,

but they protested their innocence.

There followed a court case highly influenced by politics

at which conflicting

and inconclusive evidence about the cause of the disaster was heard.

Eventually on appeal, the defendants were acquitted.

For almost a century this was how the story was put to rest.

That was until bernadetto banomo, the current mayor of one of

the destroyed towns uncovered startling new evidence.

Translator: Just after the collapse of the dam

in the prison at cremona, an inmate made a very important claim

saying that he was the head of a group of subversives who were

putting bombs everywhere in what was the rising business community.

A recently discovered court document from the trial suggests that

the breach in the dam was actually caused by a targeted attack.

I quickly found the document that says that the judge had

actually asked the most renowned expert in the world to do a survey

which showed that a bomb had exploded there.

The survey proved

that water pressure alone could never have caused the collapse.

It was then revealed that 75kg

of dynamite had also recently been stolen from the construction site.

It seemed that sabotage was the only realistic explanation.

Because of this lack of integrity between the materials

and the foundations, it's possible that these explosives actually

caused a much bigger event than the saboteurs actually intended.

It could have been a disgruntled worker who wanted

revenge for the vigano family

or it could have been an anarchist.

Because they were blowing up sort of power stations and power plants

all around the north of Italy at that time.

But a final theory suggests that

completely destroying the dam might not have been the intention at all.

The plan could have been to create a small leak which would force the dam

to be decommissioned.

So no-one knows for sure but all we do know is an explosion

of that kind should not have had the devastating effect that it did.

The cover up certainly spared the government a great

deal of embarrassment and criticism.

A spate of bombings in the area meant they should have provided

a guard at the dam.

Telling the truth 95 years later is something that hurts.

People looked death in the eyes,

a whole district was completely swept away. Whole families were

erased and the full story of a small village was buried forever.

Although over the years there has been much talk about repair

and reconstruction, the financial backing has never materialised

and the gleno dam remains as it was, a reminder of a terrible disaster.

When you look at the dam today, you're reminded that it serves

as a huge memorial, a memorial for ambition, but more than anything,

a memorial for the hundreds of people who died when it burst.

Near the centre of Detroit, Michigan is a sprawling landscape of deserted

buildings which have been left to crumble for decades.

Towering above abandoned streets, this line of structures stretches

for more than a kilometre.

What's most striking about this structure is its size.

It seems to go on forever.

It looks like some kind of industrial Metropolis,

a relic from a world that's long been forgotten.

It is complete devastation, block after block after block.

Roofs have fallen in, water is flowing on the floor,

there is no glass in any of the windows.

Nature has taken its course.

Something big happened here, almost out of a horror movie.

Inside are vast,

desolate open spaces which have been ravaged by the elements.

There's something about these cavernous, empty rooms,

it's like a film set from 'blade runner' or 'the walking dead.'

it is an incredible place and clearly has really suffered

over the years.

But what was this collection of buildings used for?

And what caused this devastation and their downfall?

The answer lies in the history of a product

that changed the face of the United States forever,

the motor car.

Until the early 1900s most travel between cities was done by rail road

by carriage or by steam boat.

But American entrepreneurs identified a huge new mass market

for an affordable alternative means of travel.

At first, development was confined to small local areas

but it soon became apparent that mass production was needed

to fully realise the potential of the exciting new invention.

In the early 20th century the American automotive industry

was very much in its infancy. Only one in every 10,000 Americans

owned a car and most of those were powered by steam.

With its vast land area and scattered

isolated settlements, the us needed cars more than anyone.

The problem was how to manufacture enough cars.

Previously factories were cramped, dingy and dirty places.

It's hard to believe now but this facility

was the start of something new.

This design completely revolutionised

the space in which you could actually manufacture the cars.

The workers had better conditions and actually it improved,

their morale and also their productivity.

The us led the way in production in terms of number and volumes of

automobiles, largely because of the factory improvements

and the ability to crank out lots of cars in a short amount of time.

The pioneering company leading the charge was packard.

Look to packard for the easiest handling car ever built.

This brilliant new facade all but drives itself thanks to packard

power steering, automatic drive and packard power brakes.

American's new choice in the fine car appeal.

This was packard's automotive plant.

Construction began in 1903 and it soon grew beyond all expectations.

The packard car plant was the most advanced auto factory in the world.

It was built over 35 acres of land

and had over 3.5 million square feet of space.

It became the gold standard for car factory design

throughout the us and production rates skyrocketed.

And the secret of its success was the use of reinforced concrete.

It was a material that transformed how a factory could be laid out,

as local tour guide Jacob Jones explains.

We are on the ground where the packard assembly line

would have been, moved through this entire space here at its peak,

going up to the floor above us, as well as the two floors below.

The blend of the steel

and the concrete added that extra support of strength

as nearly unbreakable.

This is where some of the finest luxury cars

in modern history were built.

The ones that al Capone and franklyn Roosevelt drove.

They came off of this stretch of concrete and steel right here.

But there was a problem, the price.

A packard car could cost over $3,000

when a Ford vehicle came in at just $850.

So how would packard compete?

Once again, it was down to the design of the plant

with the focus on high quality to justify high prices, practically

every part of every packard was built somewhere on this site.

The 80 skilled trade departments, an absolutely massive number,

everything was so compact here at packard, that it was really easy to

move parts, people and cars, really, from place to place.

At its peak, the complex employed up to 40,000 workers.

The company became known as producing some of the highest

quality luxury vehicles in the us.

It created what was called the grey wolf, the first

race car that was commercially available in the United States

and ultimately became a symbol of packard's success.

During its early years, packard went from strength to strength.

But the market changed in 1929

when the wall street crash shattered the economy.

Suddenly the money was drying up.

Would they be able to adapt to compete with the likes of Ford?

So, in the 1930s

packard began to try its hand at the production of cheaper cars.

Then suddenly,

the outbreak of the second world war put the whole industry on hold.

In 1942, like other car factories, it stopped producing cars

and instead focussed on manufacturing

rolls Royce aircraft and naval engines for the us and its allies.

These automotive factories shut down car production for

a few years, building just over 100 cars during world war two

throughout the entire country.

In many ways the packard car plant

and other factories like it were very, very

integral into the winning of that conflict for the allies.

The post war years were highly competitive.

The big three,

Ford, general motors and Chrysler still dominated the mass market.

But the designs of luxury cars were rapidly changing and packard

found itself left behind.

Popularity of packard cars declined due to its ability

to not compete with other luxury car manufacturers.

They started to get a bit of a reputation for

their cars not being as attractive as perhaps they could be. Some were

called pregnant elephants, some were described as bath tubs.

The cars were not popular with the public now.

With falling sales

and its reputation taking a beating, a desperate bid for survival in

the mid-1950s saw packard move off this site for good.

This great facility which had enabled it to thrive

was left abandoned and the company soon folded.

Ultimately, Ford style and price had won out against packard's more

expensive models.

From what remains today, it's hard to imagine that this

facility forever changed the way cars were built.

After packard's closure, another company occupied

part of the building for a time.

But without a solid ownership group overseeing the entire site,

much of it soon fell into disrepair.

You look at what it's become now and it really is a shadow

of the world it once knew.

It's a good example of how the mighty can easily fall.

In Eastern Europe, just over 48km from Estonia's capital, Tallinn,

is a bizarre construction lying just off the coast.

Stretching out across the water is a set of long concrete platforms.

Tucked away in a secluded corner of the world,

no-one really knew what went on there.

It was all very top secret.

When we were young playing on the beach

and suddenly 200m from us, du, du, du, du, du, du, du.

We were really like "oh, what is this?"

Almost no clues remain to indicate

what this strange structure on the edge of the sea once was.

It's like a carcass been stripped bare by the harsh baltic winds.

Something fairly serious, something fairly major was installed there.

This wasn't just your typical industrial commercial port.

I don't know exactly what was the buildings meaning but it goes

three floors under the water.

But why is this place still shrouded in secrecy

and what finally caused it to be abandoned?

The answers are linked

to the tension-filled years of the cold war.

It began with the Truman doctoring,

announced in 1947 by president Harry s Truman,

which stated as foreign policy the usa to counter Soviet expansion.

What followed were years of suspicion and mistrust

between east and west, all of which were played out against the backdrop

of the threat of nuclear war.

The cold war's most

dangerous moment came in 1962 when the Soviets deployed ballistic

missiles on the island of Cuba just 140km from the us mainland.

As the crisis unfolded, the Soviets deployed submarines, some armed with

nuclear missiles, to hold tactical positions in the Atlantic ocean.

One of the hottest parts of the whole cold war

was the undersea war,

the submarine war.

The submarine is one of the original stealth weapons

effectively. By going under water it can remain

invisible and then get very close to an enemy shoreline, enemy naval

base, launch some kind of attack.

The world was teetering on the brink of all out nuclear war.

But the waters around Cuba weren't the only place feeling the heat.

Just over 8,000km in the baltic sea,

the action was already well underway.

The baltic was still a really intense area of activity.

That the Russians needed this

baltic area to train up and practice with their

submarines and to develop better submarines and better techniques.

In Soviet-occupied Estonia this site was built to enhance

the capabilities of the Soviet fleet.

This was hara submarine base.

Completed in the late 1950s it was once a state of the art

top secret facility.

But the battle in the baltic was not all focussed on fire power.

It was also about secrecy and strategy.

Unlike a surface vessel where you designed that

for speed and efficiency, a submarine you designed for silence.

The baltic was the forefront of intelligence gathering.

Submarines were creeping along the coast,

morning, noon and night, to spy on

the military capabilities, to tap into communications.

They were both equipped with missiles that could be used to

target land sites, plus they had torpedoes for attacking warships.

But I think their spying role was probably critical.

Today the site is a shadow of its former self.

But local politician artur talvik can still picture what it used to

look like.

Everything here was full of cables.

Those two quays were united by Bridges with special cranes

moved here, back and forth to cover the ships with the cables.

Hanging huge quantities of cables across the submarines

is an unusual practice.

This is not part of standard repair and maintenance work.

So, what was going on here

and how did the base help with spying in the baltic?

The whole thing about the submarine is making it difficult to find.

The problem is its made of steel

and any steel object moving through the water is gonna generate

a magnetic signature, and that can be detected.

Hara was built to solve this problem.

It's essentially a base that demagnetises,

that reduces the magnetic signature of Soviet submarines so that they

can sneak up quite close to NATO naval bases and still

remain effectively invisible. The actual demagnetising

is actually a pretty quick and efficient process.

Getting the submarine into the lock

and lifted up, that takes all the effort.

So, the submarines came in here

and then they were checked, what is the magnetic field situation.

You establish your cable system around it,

you run the currents through that and that will lower the magnetic

signature of the submarine which can then go on its merry way.

With this process completed,

the submarine would now be much harder to track.

But this wasn't only to help it avoid detection by the enemy.

These waters also contained other deadly threats.

The first need for the base like this

was because of the magnetic mines

not far away from here.

1941 was one of the biggest sea battles in all history.

It's called (Indistinct), the mine battle.

It's estimated that during

the second world war, almost 70,000 mines and other explosive obstacles

were laid in the nearby area of the baltic sea.

And it's likely that a number of the magnetic versions were

still there.

A magnetic mine can sit there dormant, not being affected by

anything until a ship comes.

Its trigger mechanism is set to respond to the magnetic signature

of a vessel coming within range and this detonates.

The demagnetisation

only lasted for so long before the signature built up again.

And the process had to be repeated.

So, could this one base really cope with the Soviet's needs

or is there more to the site than first meets the eye?

The demagnetisation doesn't happen only here in

the quay, but also in the bay area.

There were 18km of cables here,

they spent maybe a week or even more just moving

back and forth and then they came into the harbour and measured each

ship enough demagnetised or not.

As the cold war progressed,

hara played a key role in the secret battle for position and information

that took place beneath the waters of the baltic.

But today, with the collapse of the Soviet union more than 25 years

in the past, why is there still an air of mystery surrounding the site?

The Russians were quite paranoid about anybody finding out about

their submarines.

No foreigners were allowed within any distance of this.

No-one was supposed to see what was going on.

The fact that it was doing this crucial role in trying

to reduce the magnetic signature, make submarines harder to detect,

meant that it really had to be a very top secret installation.

But these concerns didn't end with the cold war.

As the Russians withdrew and the occupation of Estonia ended,

bases like this were stripped of their assets to prevent the leak

of military secrets.

The little that remains at hara today offers only a glimpse

into the past life of the facility.

The full story of this submarine base

and its capabilities will continue to remain a mystery.

In central Europe in the northeast of Poland,

is a giant concrete structure

hidden from view by the surrounding woodland.

Deep in the rural hinterland,

this decaying object sits frozen to the ground.

You'd be very confused if you came across it.

It'd be very incongruous.

This almost alien structure plopped down in the middle of the woods.

You've got all of that green countryside,

you've got that beautiful still water,

why is there this enormous block sitting on top of it?

Whatever was once trapped inside here wasn't getting out.

When you look at it from above you realise one thing, it's a mystery.

The centre is effectively a vast pool.

Is it some kind of cooling tank?

Is it some kind of power station?

Outside, it's a water course running up it,

that might be a clue.

So why build this heavy weight structure

out here in the Polish countryside?

And why was it left in the woods, abandoned and forgotten?

The first clue to solving the mystery

can be found carved into the face of the concrete.

When you're looking at the structure

you see the concrete's been

bleached by time but in the middle of it is the outline of an eagle.

Now that can only mean on thing,

this building is from the third reich,

it's a Nazi eagle.

In 1934, the Nazi's began to seize control of Germany

as Hitler dreamed of his new empire.

In late June and early July that year came the bloody Nazi purge of

the sa, its only paramilitary wing.

In a series of executions which became known to history

as the night of the long knives.

No mercy was shown as Hitler consolidated his power,

even Ernst rohm, a long standing friend, supporter and ally of Hitler

was ruthlessly murdered.

In August, president hindenburg died.

Hitler took on the combined roles

of chancellor and president and assumed the title of fuhrer.

The new empire was about to become a reality.

It began with the agricultural region of east prussia

which was marooned on its own and which the Nazis recognised

was highly vulnerable as tensions across the continent began to rise.

When Hitler decides that he wants his new empire

to be self-sufficient, suddenly it becomes really important to grow

a lot of grain in east prussia.

But east prussia is the part of Germany that's closest to Russia.

This land was the place where the opposing sides

had gone head-to-head only two decades earlier.

It was a very intense area of conflict and a very fought after

and sought after region.

If Germany is going to control its own food supply in time of war,

it has to be able to defend this territory.

But the inland areas barely had enough people to work the land,

let alone defend it.

Despite the wishes of the Germans to have this big population

east prussa, population didn't want to live there.

A lot of them were moving out and moving away.

It was a depressed farming area.

So how do you populate an area?

Well, you build an infrastructure.

And I suppose if you build it they will come.

By day I was to build the canal

which connect masurian lakes with the baltic sea.

It was just a transportation channel to move the goods.

East prussia needs transport infrastructure

to get industrial farm machinery

and fodder in and agricultural produce out.

This mass of concrete was to be a lock on the new masurian canal.

These are the remains of lesniewo gorne.

The canal was planned to run a distance of 48km

from lake manry to the lyna river.

But there was a huge difference in height between those two points.

So locks, like this one, were needed.

There's ten total locks along the canal and they could handle

craft up to 25ft wide, being raised and lowered as the craft would move

through the canal.

The remarkable thing about the lock system here

is that it rises up 300ft.

When you think about that, that is

a boat going up a hill and over the top and down the other side.

That is what locks give us, the ability to traverse

geographical obstacles that water wouldn't normally

be able to flow on.

Of all the locks along the route,

this was the largest with a level difference of over 15m.

The lesniewo gorne lock works like this.

We have two different heights of water,

the boat goes through into the lock, the gates are closed.

Water is then flooded into the lock, raising the level of

the boat to the next passage, and then the gate is opened

and the boat passes through, proceeding along the canal.

But today there only appears to be water on one side of the lock.

Were the Nazis ever able to complete the route?

It turns out they weren't the first to attempt it.

People first tried to build a canal connecting east prussia

to the baltic sea in the 1800s

but it's never economically feasible

and there's never enough government money to make it work.

Picking up where the previous efforts had left off,

the construction also helped solve another of the regions problems.

It's really a works project, this is probably a scheme that's

going to work for all of those farm labourers that were really

living on the subsistence level.

But even with an army of workers

already busy on the project, the outbreak of war in 1939

took Hitler's ambitions to a whole new level.

Hitler's vision goes from making Germany self-sufficient

to building a continent-wide empire

so swiftly

that the impetus to keep building a canal in east prussia is wiped out.

The masurian canal is just left behind.

A few years later in December 1944 when the tide of war had turned,

the Soviet army was pushing the Germans back.

In a desperate bid to slow the approaching enemy, the Nazis

began blowing up the Bridges over the unfinished canal.

The masurian canal is meant to be

a piece of transport infrastructure, it never becomes that.

Instead, for a very short while, it just becomes a barrier against

the red army and not a very good one.

Today, this abandoned structure

is hidden amongst the trees, deep in the Polish countryside.

But with the outline of the Nazi eagle still carved above

the entrance, the memory of those dark years is ever present.

Hitler's ambition to impose his concrete

industrial will on the world failed.

I am seeing an attempt to dominate the green countryside of Poland

turned to ruins.

Hitler's thousand year empire didn't even last long enough

to finish a canal.

Now they lie abandoned but once they were

at the cutting edge of engineering.

There are echoes from history in these decaying structures,

they remind us of terror and war but also of great innovation

and human endeavour.

Captioned by ai-media ai-media. TV