Original subtitles

Tom ward (narrates): An apparent paradise in Italy

designed to hold an all powerful prisoner.

It was reserved for mafia bigwigs

including one of the top mafiosi in Italy at the time.

A Maltese fortress with hidden depths.

These old tunnels formed the basis for a network of underground spaces

that would save an incredible number of lives.

An industrial monster lost in the Alaskan tundra.

It's half structure, it's half machine,

it's a burnt out carcus and you wonder

what this was used for, what it's purpose was.

And scattered remains both above and below ground

on a beautiful korean island.

This shore line is honeycombed

with these caves yet there is something more

to this island than being a tropical paradise.

Decaying relics.

Ruins of lost worlds.

Sites haunted by the past.

Their secrets waiting to be revealed.

On the shoreline of Malta is a site

that's watched over the capital city of valetta for centuries.

You see old forts all across Europe

but this is something different, something unique.

This is a fortress that is lavishly designed,

expensively designed to not only be functional

but also be beautiful.

Originally built to face one old enemy,

certain features betray a more recent call to arms.

The closer you get the more you can see

it's actually a little bit of a patchwork of buildings,

they've had to rebuild and, and change things and refortify.

But the fort itself is only part of this story.

Nearby there are tunnels hidden beneath the streets

and buildings of the city,

they're dark wet and humid and got a spooky feeling about them.

It's almost like a little underground

labyrinth beneath the city.

So, what connects these two places?

And how would they work together

in Malta's most desperate time of need?

Originally home to an order of Christian knights,

in 1565 just over a decade after being constructed

the fort was facing an unrelenting attack

by the ottomans.

The knights were vastly outnumbered,

it was something like 35,000 against less than 10,000.

It was a bloody and brutal conflict.

The siege lasted for almost a month,

in the end though the invading forces broke through.

A last band of knights found themselves hold up in the chapel,

they said their final prayers before heading out to face

what was almost certain death.

Charles debono is the site's resident historian.

They were praying for their soul, you know?

They were defending their religion, the Roman catholic church,

so this chapel was very important for them as the last chance

to pray before sacrificing themselves against the Turks.

The ottomans finally took the fort but couldn't hold on to the city.

Soon leaving the knights to reclaim and rebuild this place.

I mean the fighting was so brutal

that what you actually look at today is really constructed

after this, this time

but if you hunt around the patchwork

you can find some remnants

of the original constructs of this era.

This building, here that we are,

is the only remaining part of the original fort,

which was then later incorporated into the new fort Saint elmo.

The fort Saint elmo visible today

tells of hundreds of years of preparation for war.

But eventually the second siege of Malta would arrive.

Those extra towers and more modern editions

they show you what was to come

but that begs the question was a centuries old fort

up to the task of dealing with a very modern kind of war?

The first stage of the reconstruction began in 1566.

But the fort was in fact just one part of a far larger plan.

The fort wasn't the only piece of construction under way,

the city itself was being rebuilt as well and it all linked together.

So, in order to build this lavish defensive facility

around the harbour,

the knights of Malta commission the local Maltese builders

to start quarrying the ground underneath.

As local historian Ryan vella knows well,

this was the starting point for the city's next chapter.

We are currently underneath the city of Valletta.

The place we are visiting today was constructed way back

during the knight's period in the late 16th century.

Probably the rock that was cut from within this quarry

was used to build the famous co-cathedral of Saint John,

which was the main church of the order of the knights.

As the city itself grew taller using the quarried stone,

so too did the new fort.

There are lots of different quarries around the whole area.

For example, beneath the area of fort Saint elmo

you had the digging up of the ditch,

which that rock was transformed into masonry stones

in order to build the fort.

The lower section of the walls

are from this early period of construction

but such fortifications weren't limited to this site alone.

The walls extended all around the city

with this fort spearheading the defence

and it didn't stop there.

You can see the fort being rebuilt but then there was an upgrade 1.1

you build it again, upgrade 1.2 you go even higher,

you make it more fortified

and the very fact that this particular strategic position

was important did not change for centuries.

The underground quarries also evolved over the years,

with the final and most surprising use

occurring in the second world war.

The place was first originated as a quarry

then it turned out to be changed over into a water reservoir.

Later on, in the mid of the 20th century

it had another vital use,

which was fully exploited by the Maltese community.

In the 1930s with Malta under British control

final preparations were made both below and above ground,

tragically it would be fort Saint elmo

that suffered the first blow in Malta's fight.

When Mussolini declares war on britain and France

on 10th June 1940,

on the next day, the first Italian aircraft appeared

over Malta and dropped their bombs.

The event is important

because the first soldiers were killed

during the first day of attacks on fort Saint elmo.

The second siege of Malta had begun.

It would continue for over two years

and some 15,000 tonnes of bombs would fall from the skies.

They used these spaces,

to enlarge them and also to dig extra rooms

in order to shelter the community over here.

People can immediately go underground

and spend some hours even maybe even days

living in these small little sort of holes

that they've carved for themselves.

It was scary for sure because the electricity was very minimal.

The place was overcrowded

because you had the whole community going down here for shelter.

The city's foundations helped protect the people,

but above ground the old fort had it's own role to play.

On the 26th of July 1941

Italian naval ships were spotted approaching the fort

and the grand harbour area.

An attack was on the cards

and the guns were about to be put to use.

The twin 6 pound coastal guns hit their targets.

There were only a handful of enemy vessels

approaching that day but the fort had done it's job.

A full invasion of the harbour was never attempted,

it seems the defensive presence of the fort

was enough to deter the enemy.

It was the same reason why the fort was built in 1552

and then at the end of the great siege of 1565.

So, the role of the fort remained important and relevant

and very strategic until the second world war.

Finally decommissioned in 1972 for over 400 years

the old fort had kept the harbour safe.

Around 15,000 buildings were destroyed

by the bombing of Malta.

And tragically more than 1500 lives were lost.

If you look at a Maltese flag you'll see a George cross,

the highest medal that the British empire

gives to civilians

and that medal was awarded

to the entire population of Malta

for standing up under relentless German and Italian bombardment

throughout the second world war.

In the north west of Alaska lies an industrial wreck

trapped in a frozen landscape.

For people who weren't indigenous this is a harsh landscape,

it's bitter cold, there's snow, there's, there's frost, there's ice.

In stark contrast to it's desolate surroundings

stands an engineering giant.

It's hard to say what it is at first glance.

It looks kind of like a building or a warehouse

but then it's got something that looks

kind of like a crane off of one end.

So, you've got this mad giant steam punk set up,

you've got all sorts of things going on.

The first question you have when you look at something

like this is who built this?

Who brought this massive piece of equipment

in to the middle of nowhere,

they must have been after something of extraordinary value

to go this absurd effort.

Rising from the flat and seemingly endless tundra,

this industrial monument can be seen for miles.

As you approach you see the top, the frame peaking out,

you see rusting metal, it's a skeletal structure

that you wonder

whether it's meant to help extract something from the earth.

Bob hafner worked on this contraption for 25 years

and still remembers the first time he laid eyes on it.

So, the first time I'd seen one of those

I came here working for the airlines

and we were flying over the tundra and it was just bare tundra

for miles and then we came over the top of a hill

and seen what looked like a small village.

And everything sitting there

and I asked the pilot, I said what is that?

He said a dredge camp.

This is dredge number five,

a modern solution to a centuries old problem.

How to pull gold out of the ground.

It's found less than five miles outside the city of nome,

once a lawless frontier town

and site of the last great north American goldrush.

This is nome, Alaska,

a city that sprang up out of almost nothing

practically overnight for one reason, gold.

In September 1898 they discovered gold in this area,

suddenly gold prospectors came in from Europe,

from the rest of the america, from the San Francisco,

from Seattle

and even from as far away as Australia.

Just getting to nome was an adventure of a lifetime.

From Seattle it was either a treacherous two week boat ride

or an even longer land journey.

Finding the gold when you had arrived though

was surprisingly simple.

Here in nome, a few prospectors realised

they could literally find gold on the beach.

The very fact that the gold was found on a beach here,

that information flew around the world

yeah because if anyone was looking for gold it's hard work

and you have to stake your claim.

But on a beach there are no claims, it's every man for himself.

Within just a few months this little village of nome

had turned in to a city of 20,000 people.

This new city was a wild and boisterous place.

It had it's bars, it had it's clubs, it had it's brothels.

This was a rough tough frontier town.

Alaska still was a territory, it wasn't a state

so there wasn't much law up here.

Eventually they sent in a, a contingency of the army

er, to try to keep rule, it's a lot of claim jumping,

a lot of back stabbing

you know, gold especially when you get hungry

can turn men into something we don't want to admit we are.

At the turn of the 20th century searching for gold here

was mostly a very basic manual process.

Had simple means what's called a rocker and a, a...

A bucket that they would flow water over the top

and put some dirt in there and shake it back and forth

while they add a little bit of water to it.

It teaches you Patience.

Tolerance of this painstaking method did not last long.

Prospectors and engineers

soon began looking for more efficient ways to extract the gold.

As the easy pickings got taken,

bigger companies started moving in...

With serious investment in machinery.

It takes on a more industrial scale

that becomes a different beast really,

a more rationalised way of extracting

the resources from the land.

Dredge number five built in 1941 was a new breed of machine

that revolutionised the hunt for gold,

it could dig deeper,

faster and longer than any human with a pick and shovel.

On the front of the dredge here you can see the bucket line

which is a lot like a chainsaw,

it has a series of buckets linked together

and rotates in a big circle driven by a motor on the dredge

and it picks up the material from the pit.

But it did more than simply dig, it was a factory too.

Inside the dredge larger rocks were filtered out

before the gold was then separated from this finer mixture

by running water through a sluice box.

A lot of fine gold would wash out

which was what we really have around nome here,

it's mostly a real fine gold erm,

like salt pepper shaker kind of size pieces.

If you can move enough material every day

it could be worth investing a huge amount of money

in building a dredge like this.

But there was only so much gold in one place.

The dredge needed access to untapped ground.

What's amazing about these dredges and if you haven't seen one

I think this is the incredible thing,

is that they move.

There's no way you could put big enough wheels on this thing

to roll across this rugged terrain.

But if you can dig a pond then you can float the dredge

and then you can keep expanding your pond

as you move forward.

But the frozen ground surrounding the dredge was a major obstacle.

Thawing it involved the construction of huge ditch lines

that bought water in from 70 miles away

and once afloat moving the dredge was still a complex procedure.

What we have on the sides here,

what you're looking at is the winchlines

that are there to pull the boat back and forth,

there's a series of winches that one pulls forward,

two pull sideways like this.

Incredibly this mechanical beast actually walked.

And what it has on the back that you can't really see

from this angle are two spuds.

One spud would drop down and lift the other one up

and so it would alternate and walk, the dredge would walk forward.

Shuffling this giant structure even a few metres

was a huge amount of work.

But all this effort was worth it when gold was struck.

There's nothing more satisfying

when you get that first bit of gold and...

And it's in your hands and you're looking at it and this is yours

and you can take that almost anywhere in the world

and use that for money.

Despite it's decades of success, the profitable years would not last.

Often the price of the thing that you're mining is going down,

there are people mining all over the world,

the supply is increasing,

you're not getting as much out of the ground

that's not a great combination.

It extracted millions of dollars of gold

from the ground here

and the town of nome has survived

and thrived over the years because of it.

Shutdown in 1996,

dredge number five now lies as a silent reminder

of a golden age.

For people like Bob it's not just the hunt for gold

that keeps them here,

it's something that runs a little deeper.

I love nome, I love the region, I love the people.

So, I've, I don't really plan on retiring anywhere else,

if I made my million I'd spend it here at the grocery store.

On the island of jeju off the southern tip of South Korea

is an area littered with strange features.

They look almost natural in the way they're kind of carpeted in grass

but they're too symmetrical

and they're laid out in some kind of a pattern.

You can see one after another

more than a dozen of these structures

which are not part of the terrain.

These unusual forms however are not alone.

Looking along the coast we see these evenly spaced caves,

dug in to the rock of the island and sort of disappearing

in to the island out of sight.

Very symmetrical, all sort of the same size openings

so they don't look like natural caves.

These cave structures are all over the island,

this shoreline is honeycombed with these caves.

Forgotten for years,

only recently has the full picture been pieced together.

You start to see that this whole island

might be hiding something.

These strange little helices on the plateau,

these strange caves along the coast,

they all tie together in the same story.

The first clue to what happened here

is found within these small grass covered mounds

that date back to the second world war.

If we look at the actual opening in to these hills

it's shaped like an aircraft

with a cut out for the fuselage and for the wing span

so basically these are hangars.

Local resident Lee yun-heong has scoured this land for clues

relating to the site's past life

when Korea was under Japanese occupation.

Lee translation: "There were fighter planes

"in this hangar like zero...

"Fighters or naval bombers.

"A total of 36 hangars were built on this airfield."

While today the surviving 20 hangars

are the most prominent reminders of this time,

hidden all around are other ruins.

"There is an airfield runway, an underground bunker,

"anti aircraft bunkers and many other facilities

"within a 1 kilometre radius of the airfield.

"Such a concentration of military facilities

"like this is hard to find anywhere else."

These are the remains of alddreu airfield,

a key part of Japan's operation seven defences.

Translation: "Number one to number six

"were operational areas in mainland Japan.

"However only jeju island was included in number seven.

Most of what we're seeing here is infrastructure

from late in the second world war when Japan shifts it's focus

to defending the Japanese home islands from allied invasion.

Translation: "Jeju was the only place outside of Japan

"that was included in the mainland's final defensive plans.

"That shows how much Japan valued the defence of jeju island."

From the moment the occupation of Korea began in 1910

Japan had ruled with an iron fist.

For those living in the south of jeju

the regimes brutal approach was felt

with the establishment of this airfield.

Translation: "The first phase of the airfields construction

"began in 1926.

"There were six villages here in jeju-do

"and the residents from each of those villages

"were evicted to make space for this airfield."

Japans treatment of the locals on jeju

was like their treatment of the locals

everywhere they occupied.

It was absolutely brutal,

they would force all the men into slave labour

and the women of jeju were forced in to prostitution.

The famous comfort women that the Japanese military demanded

to take care of their soldiers.

So, when the Japanese armed forces decide

that they need to use this area for an airfield,

they shave it flat

and they do that not by using industrial machinery

which is in short supply but by using korean forced labour.

Translation: "There were hills all over,

"however many residents of jeju

"were called up for forced labour to flatten the landscape here.

"The workers lived around here and did not have much to eat,

"there was a lot of hunger

"and there were many casualties in the process."

Japan held little regard for the locals wellbeing,

their focus was firmly fixed

on exploiting this islands potential,

a potential that explains why jeju became so important

to their later defensive plans.

If you look at jeju island on a map

it's just in an unbelievably strategic location,

it's right smack in the middle of the east China sea

between Japan and mainland China.

If you wanted to build a base that would allow you to dominate

that whole region this is where you'd put it.

In the 1930s Japan was on the front foot

and looking to expand,

as they did with the invasion of China in the sino-Japanese war.

When Japan goes to war with China they need forward air bases,

this is an ideal spot

because it takes you part way to China

so that targets in manchuria

are bought within the range of Japanese air power.

But a few years later

when Japan was losing ground in the second world war

the role of the island was flipped on it's head.

Translation: "The airfield was originally built by Japan

"because of the sites geographical importance.

"That's why Japan's strategy was to think of jeju island

"as an important defensive base for the Japanese mainland battles

"and to devise and prepare for the mainland show down."

It's envisioned more and more as a sort of iwo jima type place

where the Japanese will mass ground troops

to fight a last stand against the Americans

who will be forced to attack it because of it's strategic location.

In January 1944

there were just 300 Japanese troops stationed on jeju

but that number was about to sky rocket.

By mid 1945 there are 70,000 Japanese troops on the island,

a third of the, the total number of Japanese troops

on the whole korean peninsula.

The Japanese defence concept

was that the invader might land on the island

but that the island might then become a living hell for them.

Once again the local population

was forced to carry out back breaking work

as a new network of defences and subterranean bases

were carved out of the island.

Translation: "This is a large underground bunker

"built by the Japanese.

"It was big enough for vehicles to pass through,

"there were important facilities here

"including the command headquarters of the airfield

"and a torpedo storage facility."

This single underground facility stretches on into the darkness

for 3 quarters of a mile.

But it was just a fraction of the true extent of the defences

hidden beneath the surface.

Translation: "In jeju there are about

"700 underground tunnels

"dug by the Japanese during the pacific war."

As the so called operation seven got underway

the foremost defensive tunnels

were cut right in to the island's cliffs

and they harboured a deadly weapon.

They begin carving out these caves for these mini submarines

that will launch under sea kamikaze attacks against American warships.

Translation: "These bases were used to station boats

"loaded with over 500 pounds of explosives,

"they would be driven by a soldier

"and used as a suicide bomber boat against the us ships."

The idea that somebody might give his life

in order to sink an American destroyer

using himself as part of a weapon,

that idea was genuinely disturbing

to Americans and very effective

both as a propaganda tool and as a military reality.

In the last years of the war,

it's estimated that over 7,000 naval personnel

were killed by aerial or seaborne kamikaze attacks.

It was a devastating tactic but it came at a huge price.

And it may help explain

why so many of these military positions here

are still intact.

In a way though all these kamikaze missions

might have backfired on the Japanese,

it convinced the Americans

that the Japanese military would never surrender,

that they would fight to the last man.

Taking the Japanese home islands to end the war

would have killed millions.

Using atomic bombs to end the war killed thousands.

The choice wasn't easy but the choice was clear.

The allied invasion of jeju at the beginning

of the allied invasion of Japan, that carnage was avoided.

What remains on jeju are some of the best examples

of Japanese pacific war infrastructure still in existence.

And now these remnants from that brutal occupation

have a far greater purpose.

Translation: "I hope people around the world

"will recognise these facilities

"as places to reflect on that original war of aggression.

"The violation of the human rights of those enslaved

"and the importance of peace."

Off the coast of sardinia is an 11 mile long slither of land.

A haven for nature and wildlife.

This island is a bit of a paradise, the lush vegetation,

the waters it's not surprise that it's a national park.

When you first come on the scene

this looks like an idyllic mediterranean island

with little rocky outcrops and olive trees.

Yet beyond this pastoral beauty

lies a series of abandoned buildings,

although virtually uninhabited by man today,

they suggest the island once housed a significant population.

One particular building looks like it might almost be...

A monastery or religious retreat.

It's very inward facing but then you see the barbed wire,

you see the guard towers, inside you see the locked doors,

you realise this is no monastery.

Eight miles away at the northern end of the island

is a second structure with strange design features.

The closer you look you realise

that this wasn't just any old prison,

you have these huge high walls, the guard towers,

the spotlights and just one tiny hatch

for an entrance.

Within it's outer walls the mystery deepens.

There are hardly any windows or openings to speak of...

And from above you can see there's a secondary inner structure,

almost a prison within the prison.

Whoever was held here was dangerous indeed.

So, how are these two sites linked

and who was locked up at the heart of this complex?

On the southern end of the island,

a large rectangular building

is ominously surrounded by search lights,

metal bars and smashed guard huts.

Today access inside is strictly forbidden

but former prison guard gianmaria deriv

remembers what life was like for those on the inside.

Gianmaria translation: "Less freedoms, less space,

"the procedures are really strict.

"So, they can't leave the building at all,

"everything takes place inside."

This is forneli prison,

a maximum security facility where guards like gianmaria

could keep inmates on a tight leash.

Translation: "Bringing them to an island on an island

"we could say it was like cutting the umbilical cord."

Separated from the mainland by 180 miles of open sea,

the Italian government

saw the potential for this site as a place to lock up

Italy's most dangerous criminals.

Translation: "Originally it was a judiciary sanitorium

"and tuberculosis hospital

"but then with the emergence of red and black terrorism in Italy

"the government decided to turn this facility

"in to a supermax prison."

Extreme left wing groups known as red terrorists

were leading a wave of violence across Italy in the late 1970s.

Revolutionaries attempting to overthrow the capitalist state

and force Italy's withdrawal from NATO,

the north Atlantic treaty organisation.

They had home grown ultra left wing

terrorist groups like the red brigades,

they were literally going to war against the country

and against the government.

In 1978,

they even assassinated former Italian prime minister

Aldo moral...

As members of the organisation were rounded up in response

the government increasingly turned

to the isolated island of asinara

and used fornelli as a dumping ground.

They sent so many members of the red brigade

to the fornelli prison

that it became a huge focus of the group

to get those people released.

September 1979,

a clash broke out on the streets of Rome.

There was a huge shootout between red brigade forces

and the authorities

and when one of them was captured he had on him

this whole elaborate plan for a mass escape

from the fornelli prison,

they were going to smuggle in machine guns,

they were gonna have motor boats,

they were going to overwhelm the prison

and get all these prisoners out.

The plan had been scuppered but members of the brigade

inside fornelli took matters in to their own hands.

Rioters destroyed cells

and smashed sections of the building.

Translation: "They had packed their stove top coffee machines

"with explosives and plastic.

"They had managed to create real bombs."

Riot police on horseback surround the maximum security wing.

Translation: "There were tense moments

"but you weren't supposed to show fear."

Tear gas was launched in to the heart of the uprising.

Translation: "The red brigade attempted a rebellion

"and then tried to leave the facility but they failed,

"they surrendered at about 3am."

The riot was quashed but soon after without warning

the authorities transferred all the terrorists off the island.

They began replacing them

with Italy's new public enemy number 1,

mafia bosses.

But to handle them they were going to need a new facility.

Enrico translation: "At the end of the day

"we were selected.

"500 guards were chosen because of this situation."

Enrico mereu was selected as head guard of a new specialised facility.

Look out towers stood at each corner

while walkways around the perimeter left no area out of sight.

But at the centre of the facility

was one particularly strange feature.

A new area was added to the design, the bunker,

built with reinforced concrete and surrounded with barbed wire.

The bunker was a singular prison within a prison,

a tiny villa built within high stone walls

and only one small entrance.

It was designed to house just one man.

That's where the top mafia boss or bosses were sent,

where they could really be isolated, you could keep an eye on them,

you could also protect them from being executed

by other forces or poisoned.

The bunker was reserved for the top dog,

the last great sicilian mafia chief,

Salvatore riina who was the head of the corleonesi clan.

He came from corleone in sicily

and that is famously associated with the godfather trilogy.

Riina had gone to war with the state,

targeting top officials

and organising terrorist style bombings.

As the government fought back just as it had with the red terrorists

this island became it's main prison for mobsters.

Riina was given 26 life sentences

for the murder of hundreds of individuals.

Two of riina's victims enrico had known personally.

Translation: "It was an awful experience for me,

"I found myself here with riina,

"the instigator of those murders."

Riina's influence was such that even within prison walls

he could wield great power.

For a lot of Americans whose idea about the mafia comes from

you know, the godfather movies and things like that

it's hard to appreciate just how powerful the mafia was...

Up until really quite recent times,

it was almost like a shadow government.

The surrounding area was patrolled by 100 agents,

boats crisscrossed the sea day and night,

threats from the sky were monitored with radar.

Controls within the bunker had to be equally water tight.

Translation: "So, every time we entered or left the bunker

"we had to search each other.

"In fact there were no friends allowed here."

Even his food was bought to him in a special briefcase

to avoid attempts at poisoning.

We always hear a lot about codes of honour among the mafia types

but history shows that provided with the right incentives

they'll turn on each other in a heartbeat.

Protocols were designed to prevent corrupt guards

carrying out assassinations on behalf of rival mafiosi

looking to take riina's crown.

Translation: "We couldn't carry cell phones or paperwork

"that might endanger you by revealing your identity.

"We couldn't talk or mention names of wives or daughters.

"Nothing at all.

"We talked only about the service,

"that was it."

Prison is brutalising for everyone, these prisons were,

were terrible places for the prisoners

but also for the guards who were in fear for their lives

and so isolated, so far away from normal civilisation,

it had to have been a very rugged existence.

The real need for this extreme isolation

was not about preventing escape but getting them to turn informer.

They isolated them so thoroughly that the idea was they would realise

wait if I'm facing 20 years

where I can't talk to any of my associates,

I can't do any of my former business,

I might as well become an informant and maybe get out earlier.

Yet riina never turned.

Enrico hand delivered his dinner in an armoured briefcase

every day for 4 years.

Until the prison was closed down in 1997.

By the late 90s the tide of violence

from first the red brigades and then the mafia

was receding and law enforcement was getting the upper hand

and they realised they didn't need this kind of ultra security

er, prison to the same degree.

The so called beast lived out his days in a different prison

in solitary confinement.

At the time of his death in 2017

some claimed that tota riina was still operating

as the head of sicilian mafia.

Today, asinara is a national park,

home to the rare albino donkeys that gave the island it's name.

The dilapidated prison structures

are preserved as relics of a very different time.

One that is thankfully consigned to the past.

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