NARRATOR: They're watching you.
More than 5,000 satellites circle the Earth.
Every day, they uncover new, mysterious phenomena
that defy explanation.
Witches, kings, and mega weapons
in a 1,000-year-old forest.
Strange symbols have been found here.
What is this?
NARRATOR: Decoding the great plagues of Egypt.
It all happened just a few miles
from where this image is located.
NARRATOR: And the super warriors of Voodoo Lake.
It was referred to as the Sparta of Africa,
because this was a society of brutal warriors.
NARRATOR: Baffling phenomena, mysteries from space.
What on Earth are they?
[theme music playing]
NARRATOR: The New Forest, South Central England,
a vast expanse of woodland and wild gorse,
barely changed since the Norman conquest of England
in 1066.
People haven't been allowed to build here,
by royal decree, for over 1,000 years.
NARRATOR: Yet on June 5th, 2010,
an aerial LIDAR scanner reveals remnants
of a seemingly man-made structure buried
in a barren valley.
The image is really bizarre.
It's multiple concentric circles made up of
a series of smaller circles, really reminiscent
of a dartboard.
How long has this pattern been there?
How many ages has it been laying,
waiting to be discovered?
NARRATOR: Hooked by the weird circles,
archaeologist Rebecca Bradshaw is
trekking into the remote forest, which is anything
but new.
BRADSHAW: The forest has this extraordinary history.
It's a really ancient, spiritual space.
NARRATOR: In 1079, King William The Conqueror claims
this region as a royal hunting ground.
Peasants are driven out, threatened with death if
they disobey.
But death finds William.
Two of the king's sons meet their end here,
one slain by a hunter's arrow, the other in a riding accident.
The locals said that this was God's will
punishing him, because he removed
13 churches and scattered all the inhabitants,
making New Forest almost barren of people.
NARRATOR: But some return and make their mark on the woods,
leaving clues Bradshaw thinks could shed
light on the LIDAR image.
Strange symbols carved into trees and things
have been found here
and have confused a number of historians looking to document
the history of the New Forest.
NARRATOR: In the 18th and 19th centuries,
trees suitable for shipbuilding are
carved with the king's mark,
a broad arrow.
But there are also older carvings,
strange shapes, some of them reminiscent of the LIDAR image,
the work of medieval misfits,
spiritual outcasts who come to convene with the ancient forest.
On some of these trees,
they found concentric circles that
historians identify as witches' marks.
A square has corners and edges, whereas a circle doesn't,
and so it's a way of capturing evil,
circumscribing evil into one particular place.
NARRATOR: Evidence of witches' marks
can be traced to the early 1300s.
They are found in caves and medieval buildings
across Britain,
scored in the wooden beams of churches and domestic dwellings.
HYMEL: Witches would also carve them into the ground,
from where they would then conduct their spells.
HORTON: It is possible that these concentric circles
we see in the LIDAR image
is an example of these protection marks that you find
on trees and on buildings.
NARRATOR: But if these have been left by witches,
they are massive.
The largest is almost a mile wide.
They are of a size, scale, and precision
that really suggests a much more modern effort.
NARRATOR: Closing in on the site scanned from the skies...
What is this?
Bradshaw finds further evidence that the strange
circles may be much more recent in origin.
On first glance, this, to me,
looks like extremely heavy duty concrete,
and the shape, of course, suggests...
[sniffles]
A bunker.
This is a bit odd, because it hasn't got
any visible
signs of where guns could go.
What is a non-defensive bunker doing here
in the middle of a pretty dense wooded area?
NARRATOR: Climbing out of the trees,
Bradshaw reaches a vantage point high above the valley
in the LIDAR image...
Well, well, well.
where she finds a bizarre clue
that literally points the way.
This
looks to me
like 100 feet in length by sort of 30
to 40 feet wide, and it is pointing directly
into this valley here.
This is crazy.
NARRATOR: Up close, the giant arrow
serves no apparent purpose.
But Bradshaw considers a fresh perspective.
If you're a pilot coming through the skies,
you have indicators on the ground like this arrow to
direct you where you're going,
then it would make sense that those concentric circles
are actually a massive target.
NARRATOR: A mild descent into the valley...
Wow!
and Bradshaw's theory hits the bull's eye.
This is a bomb crater.
I get the feeling that this is a Second World War
bombing range.
NARRATOR: But this is no ordinary bombing range.
The archaeologist estimates the width
of the crater at 100 feet plus.
It could easily be over 50 feet deep.
Something really quite extraordinary
was dropped here to make this size crater.
NARRATOR: Bradshaw has found evidence of
a cataclysmic experiment that rocked rural England.
What the British army did in the New Forest
was secret then, and had remained secret
for decades afterward.
Coming up, the mega blast that changed history.
The Germans didn't know what hit them.
NARRATOR: And blood of the mummies.
KOUROUNIS: It looks like some gigantic footprint
has just smashed into the desert.
NARRATOR: Archaeologist Rebecca Bradshaw
is in England's ancient New Forest...
This is a Second World War bombing range.
investigating strange circles revealed by LIDAR.
BRADSHAW: Something really quite extraordinary
was dropped here to make this size crater.
NARRATOR: During World War II,
U.S. and British forces drop around 1.5 million tons of
bombs on Germany.
A single raid
could see up to 1,000 planes
unleash their fury on German cities.
So Hitler moves underground,
building impregnable mega structures across
occupied Europe.
The Germans built a whole series of structures that were
immune to all the bombs that the British had then developed.
The most famous of these were the submarine pens on
the French coast at Saint-Nazaire,
with concrete ceilings 10 feet thick.
NARRATOR: To break through, Britain needs
somewhere to test experimental bombs in secret.
Empty by order of William the Conqueror,
the remote New Forest is ideal.
This LIDAR image shows an essential
part of the Ashley Walk Bombing Range.
NARRATOR: According to declassified military records,
Ashley Walk becomes operational in 1940.
Hell is soon raining down onto vast chalk circles.
MORGAN: The concentric circles in the image
were a method of evaluating the effectiveness of extremely
powerful bombs.
You can measure the distance from the epicenter of
the explosion, and it allows you to determine
just how effective the weapon is going to be.
The most important person involved in this
testing was the legendary scientist Barnes Wallis.
Dr. Wallis masterminds the revolutionary bouncing bomb,
tested at Ashley Walk,
which wipes out two German power stations beyond the reach
of conventional ordnance.
HYMEL: Thanks to Barnes Wallis, these so-called
impregnable defenses are no longer impregnable.
And Dr. Boom is just warming up.
There's only one bomb that I can think of that had enough
power to generate a crater like this,
and that is a Tallboy.
NARRATOR: Wallis's six-ton Tallboy is a game changer.
WALTERS: It really was a big bomb.
In fact, it was what was known as an earthquake bomb.
The earthquake bomb didn't need precision.
It set off such giant shockwaves that it would
destroy targets for hundreds,
if not thousands, of yards around.
NARRATOR: The Tallboy, tested at the LIDAR site,
is first deployed in June 1944.
854 will fall by
the end of the war,
wiping out bridges, dams, and V-1 launch sites.
ANNOUNCER: We see the Tirpitz firing
back at them with 15-inch guns.
NARRATOR: Tallboys also sink
Hitler's prime battleship, the Tirpitz.
ANNOUNCER: Watch for the 12,000-pounder
that stopped those guns once and for all.
NARRATOR: While at the New Forest,
Wallis is preparing to test something even bigger.
I mean, look at this extremely
heavy duty concrete and this rebar here.
Really designed to take a hit.
I'm willing to bet that another type of earthquake bomb
was also being tested here, and that's called the Grand Slam.
NARRATOR: Weighing more than some tanks,
the Grand Slam is nicknamed Ten Ton Tess,
and she's devastating.
The Grand Slam was only tested once before
it was used over Nazi Germany, and it was tested here in
the New Forest,
and that was one of the biggest explosions that's ever
happened in the British Isles.
NARRATOR: On March 13th, 1945,
an experimental Grand Slam smashes into the targets on
the LIDAR image at 700 miles an hour.
Nine seconds later, it explodes, triggering a massive
artificial earthquake.
SILBEY: The test of the Grand Slam bomb
was so successful, the Allied High Command decided to send
the bomb into action the very next day.
They took out viaducts, coastal defenses,
even submarine pens.
The Germans didn't know what hit them.
They thought their sub pens
and their batteries were completely impregnable.
The Grand Slam bomb was incredibly effective at
destroying Nazi architecture
and infrastructure and really helped turn the tide of
the war.
SILBEY: As soon as the Americans saw the success of
this new kind of British weapon,
they created their own version, the T-12 Cloudmaker.
NARRATOR: Twice the size of the Grand Slam,
the 20-ton Cloudmaker never sees action,
as it is quickly superseded by nuclear weapons,
but earthquake bombs make an earth-shattering
comeback in the run up to the 1991 Gulf War.
Iraqi despot, Saddam Hussein, has read Hitler's playbook
and built a fortified mega bunker underground.
The United States deploys this new weapon called the GBU-28,
which is gonna become known as the bunker buster.
SILBEY: The GBU-28 destroyed the Iraqi bunker.
At its basic level,
it was identical in effect to what Barnes Wallis
had started back in the Second World War.
I don't want to imagine a World War II
that didn't have a Barnes Wallis on our side.
I put him up there with, like, Alan Turing, for example.
These people who, through genius,
helped to win the war.
NARRATOR: Barnes Wallis's genius and the secrets of
the New Forest have been exposed from the skies.
But what else lurks beneath these
ancient woodlands remains to be discovered.
Given the top secret clandestine nature of
this site, it may be that we never know.
NARRATOR: Coming up, the wrath of the female super soldiers.
HORTON: They were disciplined, organized,
and highly successful.
And mummies, Romans, and biblical plagues.
And that's what we're seeing from satellite.
NARRATOR: June 30, 2019.
Eyes in the sky over Egypt
scan a valley 50 miles northwest of Cairo.
We're seeing a beige ground, what you'd expect to see,
but then in the middle is this strange shape.
KOUROUNIS: It almost looks like some gigantic footprint has
just come down and smashed into the desert.
NARRATOR: The mega-sized print covers around
eight million square feet of the valley floor.
It's as if the earth has been bleeding,
but the wound closed up and dried.
KOUROUNIS: Looking a little closer,
it has all the characteristics of a dried lake bed.
It's not just the shape that's unusual,
it's the color.
Maybe we're seeing some mineral that was
left over when the lake dried up.
NARRATOR: Historical records confirm the presence of
a unique mineral in the lake
that could partly explain its weird coloration,
one that played a key role
in the two greatest civilizations of antiquity.
It just so happens that this lake is covered
in a layer of sulfate deposits known as natron.
NARRATOR: Some 5 and a half thousand years ago,
the ancient Egyptians begin mummifying their dead.
They encase the cadavers in natron, harvested from
the country's desert lakes,
to dry out the corpse, preserving it for the afterlife.
These natron lakes are very alkaline,
meaning these are harsh to most forms of life, and that's
what we're seeing from satellite.
NARRATOR: Natron from the lake
in the image was likely used to entomb many of the great
pharaohs and high priests of ancient Egypt.
During the reign of Cleopatra,
Egypt falls under the rule of Rome, and the mineral is
put to a very different use, one that transforms the world.
The sailors were using natron blocks to support
their cooking pots on the beach, and the heat
of the flames caused the blocks to melt,
producing glass.
And as these little streams of glass
are coming out from under the fire, boom,
the glass industry is born.
NARRATOR: For much of antiquity,
glass was as expensive as gold and precious gems,
an indulgence reserved for chieftains,
royalty, and religious buildings.
The very first glass is believed to
have been made in Mesopotamia 5,000 years ago.
That early period is almost done with a small scale.
NARRATOR: In around 30 BC,
the natron deposits in the lake attract
Roman scientists,
alchemists in glass making,
who set up vast furnaces around its shores.
Glass is mainly sand, and there's
plenty of that out in the desert.
Finding that resource, no problem, but you need
a flux catalyst.
That's exactly what we find here at this lake.
It was the Romans that industrialized glass production
on a much bigger scale,
as glass then became a consumer object that was
employed throughout the empire.
NARRATOR: Such is the value of Roman glass
that it is traded across the known world,
reaching as far as Afghanistan and China.
We're not talking about, like, some artisan making a couple
of glasses, we're talking about glass slabs
weighing 20 tons that could be shipped anywhere.
NARRATOR: The advent of glass blowing enables the Romans to
form these giant blocks into any shape or size,
revolutionizing the industry.
A single glass slab manufactured from this site in
Egypt could have been broken down
into thousands of pieces and turned into tens of thousands
of individual bottles and glasses.
HYMEL: It makes it cheaper and more accessible
to a much larger population -- It just explodes.
NARRATOR: For around 400 years,
the site spotted from space
is the focal point of Roman glass production,
creating the windows that adorn Rome's greatest buildings.
And putting bottles on the tables of the empire's
65 million citizens.
Yet the presence of natron only explains
part of the lake's strange appearance.
HORTON: Natron is a mineral salt that's naturally
white or pale yellow.
So that raises the question,
what is this red deposit that's also found on the lake?
NARRATOR: Mark Horton learns that the caustic waters
that enticed the morticians and glass makers
of Egypt and Rome also attract aquatic
organisms in their countless billions.
On the surface of this lake is an algae that can live in
these extremely hostile environments
and breeds and forms this skin of pinky red on
the surface of the white salt.
NARRATOR: When the algae blooms, it produces red pigments,
creating giant patterns on the natron lake.
These blooms also generate toxins, which are lethal
to fish, birds, and humans,
toxins which could help explain one of
the most famous mass deaths in history.
There are Biblical stories that speak
of a similar phenomenon.
God sent 10 plagues upon Pharaoh and the Egyptians,
and one of those was to cause the Nile to run blood red.
BELLINGER: The fish died, the river stank,
the Egyptians couldn't drink the water anymore,
and it all happened just a few miles from where
this image is located.
NARRATOR: The same lake that helped mummify
the Egyptians, carrying them to the afterlife,
may have also been the cause of their sickness and death.
Lots of legends are based on nuggets of truth, and it's
entirely possible that the Biblical tale
of the Nile running red could have been caused by one of
these massive red algal blooms.
NARRATOR: Coming up, attack of the man hunters.
The Europeans are utterly terrified of
these women warriors, whom they called Amazons.
NARRATOR: And the Nazis' secret terror weapon.
12,000 tons is enough to kill millions and millions
of people.
NARRATOR: October 12th, 2020.
A satellite scanning the country of Benin
in West Africa
captures strange features in a lake far below.
This is bizarre.
I don't see any roads, I don't see any fields,
just homes, buildings, and water.
It looks like a settlement that's
just been overwhelmed by an incoming flood.
HORTON: But looking more carefully, I can see
that this is not a flooded village,
but actually a village that's been built
deliberately in a lake.
NARRATOR: This is Ganvie, a giant floating village of some
3,000 raised structures and the ancestral home
of the Tofinou people.
Yet what really intrigues analysts is why the Tofinou
chose to build it here in the first place.
BELLINGER: The Tofinou tribe has, for generations,
been building over water,
and we know from oral tradition that's for
an extraordinary reason.
NARRATOR: The story of the strange lake village
begins in the 17th century.
At the time,
much of this region is dominated by the Tofinou's rivals,
the Fon people, who ruled the powerful Dahomey kingdom.
It was actually sometimes referred to as the Sparta
of Africa, because this was a society of brutal warriors.
Fon warriors developed a fearsome reputation that
traveled far beyond the borders of their kingdom.
NARRATOR: The Fon rely heavily on forced labor,
and around 1/5 of their kingdom's
one million strong population are slaves.
This group of people use this military brutality and prowess
to become very wealthy and successful in the slave trade,
terrorizing any of the tribes around them that they did not
have a relationship or an agreement with.
HORTON: They were disciplined, organized,
and highly successful.
NARRATOR: In 1720, the Fon warriors push
south towards the site in the image,
putting their king in contact with European slavers.
In exchange for goods and weapons,
he supplies them with around 20 percent of
all the humans trafficked across the Atlantic.
But years of raiding neighboring states
deplete the number of male Fon warriors,
and the kingdom's enemies begin to close in.
This creates a cultural shift for the Fon people
and through that,
their women become more and more a part
of their combat force.
Women played a major role in the military,
so much so that the king had an elite group that served as
an all female royal guard.
NARRATOR: Such are the skill and ferocity of
these female warriors that between the 1760s and 1840s,
their ranks increase from 600 to 6,000.
They're the only known female fighting
force in the world at this time.
The Europeans are utterly terrified of
these women warriors, whom they called Amazons.
Their specialty was pre-dawn attacks on enemy villages,
and that was the most efficient
and effective way for them to gather up slaves
to sell to the Europeans.
NARRATOR: The Fons' slaving raids puts them in conflict with
the Tofinou people and explains the construction of their giant
lake village in the satellite image.
The Tofinou people didn't have quite the warrior culture that
the Fon did, but they were clever,
and they were observant, and over time,
they look for weaknesses in the Fon tactics and strategy.
One of the weaknesses they found was a fear of the lake.
NARRATOR: The Tofinou know that the Fon are
devotees of Vodun, the origin of today's Voodoo.
They believe that powerful, supernatural beings
inhabit nature and fear vengeful water spirits.
According to Fon tradition,
a powerful demon walked the waters of this lake,
and they would never do anything to raise that demon's anger.
KOUROUNIS: The Fon refused to attack
any structure that was on water,
so the Tofinou built their village on the water,
and suddenly, they were able to use their own superstition
against them.
NARRATOR: Over the following decades,
more Tofinou move on to the lake
to escape persecution at the hands of the Fon.
They become known as the Water People.
KOUROUNIS: As long as they lived on the water,
these villagers were safe from attack
and were able to avoid being sold into slavery.
They gave the name of the village Ganvie,
which means, in the local language, "We survived."
BELLINGER: And so the Tofinous stayed and continued to build
and expand this village on stilts
for many generations to come.
NARRATOR: 150 years after the end of the slave trade,
the water village of Ganvie continues to flourish,
a living monument to one people's resilience in
the face of unspeakable terror.
JANULIS: To this day, there are 20,000 Tofinou
still living on the lake, just like their ancestors did,
who avoided being captured by the Fon.
It's a very interesting, very horrific history,
but one that needs told.
NARRATOR: Coming up, monster tank face off.
It was one of the most incredible battles
of World War II.
NARRATOR: And the killer quarry.
It becomes a warehouse of death.
NARRATOR: October 9, 2018.
A camera in orbit over Ukraine scans the city of Kharkiv.
WALTERS: What we're looking at here
is a pretty grim-looking industrial complex,
bit of a wasteland, frankly --
It's not a very inviting place.
NARRATOR: Yet lines of objects hidden between
the desolate looking buildings do invite attention.
CAVELL: Looking closer, you can start to see
that these objects actually have
some kind of a turret on them and some sort of gun.
These are tanks.
These are armored fighting vehicles,
and there are dozens and dozens of them.
NARRATOR: Leaked photographs confirm that the image
has captured a monstrous metal graveyard,
containing the rusting remains of hundreds of tanks.
WALTERS: You've got to ask yourself why are there
so many tanks just sitting there doing nothing.
Tanks should be out fighting.
This is just a huge tank park.
NARRATOR: Martin Morgan studies the city's history for clues.
When I look into original records,
I find that this is the old Kharkiv tank factory.
This was the largest factory for the production of armored
fighting vehicles during the old Soviet Union
and the birthplace of what was one of the greatest
fighting machines of the 20th century.
NARRATOR: That fighting machine is the T-34 tank.
The T-34 tank is one of the most powerful weapons that
the Soviets wielded on
the battlefields of the Second World War.
It's a part of every battle.
It's a part of every Soviet victory,
and they're all made at Kharkiv.
NARRATOR: The T-34's engine and tracks are built to handle
mud and snow on the battlefields
of the Eastern Front.
What's more, it has a more powerful cannon and better
armor than German tanks,
but it's light enough to outpace them
on the battlefield.
MORGAN: The T-34 is arguably the finest tank of
the Second World War, because it is the best of both worlds.
The Germans were scared as hell of this vehicle,
and that speaks to just how effective
the design really was.
NARRATOR: The success of the T-34
forces the Nazis to deploy the massive 54-ton Tiger.
In July 1943, vast numbers of Russian and Nazi
tanks meet head-on at the Battle of Kursk.
About 5,000 tanks will come to this battle.
So it's the biggest tank battle of all time,
including up to today.
You have tanks just rolling towards each other, firing
massive shells back and forth.
I mean, it was -- it was probably one of the...
most incredible battles of World War II.
NARRATOR: At the Battle of Kursk,
the Russians incur devastating losses,
but the T-34s ultimately prevail.
The Germans never recover from this defeat,
and two years later, the Soviets capture Berlin.
PAVELEC: Kursk is one of the turning points that
solidifies the final retreats
and absolute route of the Germans
off of the Eastern Front.
NARRATOR: Following the end of World War II,
the Kharkiv Tank factory continues to play a vital role
in Soviet military strategy.
MORGAN: There are over 60,000 workers that are producing
about 60 tanks a month at this facility
during the height of the Cold War.
[indistinct shouting]
NARRATOR: In 1991, the Soviet Union collapses,
and countries like Ukraine gain their independence.
Tanks stopped rolling off
the Kharkiv factory line, and its yards begin filling with
mothballed relics of the country's communist past.
Yet recent analysis has revealed renewed activity
at the site.
MORGAN: When we look at satellite imagery,
we can see that tanks are kind of coming and going from
the facility.
NARRATOR: It appears Ukraine has once again turned to
the T-34 tank factory to help it repel a foreign threat.
These tanks could well be part of Ukraine's
absolutely justified efforts to defend herself against
Putin's aggression.
NARRATOR: In 2014, Russian President Vladimir Putin
[speaking Russian]
Orders his troops to invade Ukraine's Crimean Peninsula.
This triggers an ongoing war,
which has claimed over 13,000 lives.
The attack that Russia mounts on the Crimea is forceful.
They come in with aircraft.
They come in with tanks, they come in with ground troops.
NARRATOR: In a twist of fate,
Russia is now fighting tanks from the very factory
that helped it to defeat Hitler all those years ago.
MORGAN: This image is full of deep, contemporary ironies,
because it makes you confront the way that the former
Soviet Union crumbled, fell apart,
and the awkward, intense new world that has been
created in its aftermath.
NARRATOR: Coming up, magic lake.
It's as if the water had been turned to oil.
NARRATOR: April 2017.
Satellites orbiting over northern Europe
scan a quarry in England's industrial heartlands
and uncover a mystery.
RUBEN: We're looking at what
looks like a rather beautiful lagoon,
very vibrant blue.
And then you go to the next image,
and it's black.
NARRATOR: The lagoon is vast,
43,000 square feet,
but its dramatic color change has taken just a few hours.
It's as if the water had been turned to oil.
That's what it looks like.
NARRATOR: This quarry is called Harper Hill,
and it has a dark history that could explain the lagoon's
weird transformation. - PAVELEC: Interestingly,
this was a chemical weapons storage facility before, during,
and after the Second World War.
Tens of thousands of chemical weapons were stored here and in
the area surrounding it.
NARRATOR: In 1938, Harper Hill Quarry
is chosen as the location
for a facility code-named Maintenance Unit 28.
Over the following two years,
the British military use it to conceal more than 45,000
different chemical weapons.
It becomes a warehouse of death.
By 1940, it's the largest chemical
weapons storage depot in Britain.
NARRATOR: The warehouse of death has its origins in the mud,
blood, and gore of the battlefields of World War I.
JANULIS: World War I was the first example
of truly industrial warfare,
and in 1915, the first example of
chemical warfare being utilized.
During World War I, chemical weapons
kill or injure over a million soldiers,
including a young Adolf Hitler.
After World War I, the Western countries decided
that chemical warfare was so inhumane,
it should be banned,
but that didn't stop all of these countries
from continuing to experiment with chemical weapons.
NARRATOR: In 1938, German scientists discover sarin,
a compound 20 times more lethal than cyanide.
They go on to produce 12,000 tons of the nerve agent
during the war.
12,000 tons of sarin gas is enough
to kill millions and millions of people.
So places like Harper Hill acted as
that storage point for the captured chemical weaponry
at the end of World War II.
PAVELEC: Could it be that there's chemical weapons
that were not disposed of properly
that are now coming to the surface and turning
the water black?
NARRATOR: When scientists test the lagoon
in the image, they confirm it is dangerously contaminated,
but it's a legacy of a different era
in the quarry's history.
Chemical analysis has shown that it's
actually got a really high pH level.
KOUROUNIS: It's been measured at a pH of 11.3.
Pure ammonia is about 11.6.
So this is nasty stuff.
NARRATOR: Long before World War II,
the quarry produced vast amounts of highly alkaline
quicklime.
During the 19th century,
it played a vital role in creating the modern world.
JANULIS: Quicklime reacts with certain elements
within molten metal,
basically getting the impurities out,
causing them to aggregate, creating slag that can be
easily removed to get pure steel.
NARRATOR: Steel made using quicklime fuels
what is known as the second Industrial Revolution,
which transforms the industries and landscapes of
England, the U.S., and beyond.
MORGAN: So many of the things that we recognize as being part
of the greatness of modernity are created during
this critical time period,
during the Industrial Revolution.
NARRATOR: In 1952, the quarry closes,
and it fills with water,
creating the lagoon in the image.
That begins to explain a lot about the color of this water.
That deep blue can come from calcium carbonate
that leaches out of limestone.
KAYS: Now we understand why it's so beautifully blue,
nut the question remains, why did it suddenly turn black?
NARRATOR: As news of the azure lagoon spreads,
it attracts thousands of visitors, and its caustic waters
become fetid with all manner of garbage and waste.
RUBEN: The blue color is really beautiful,
but this lagoon has also been used as a dumping ground for
the bodies of animals, car wrecks,
whatever people have decided to throw in there.
KOUROUNIS: The authorities actively try to dissuade people
from swimming in these waters,
but all of the signs and warnings have little effect.
So what do you do?
Well, the authorities have gone to the extreme
steps of having to dye the water black.
KAYS: They bought some dye.
They dumped it in, the next day, when the revelers showed up to
hang out by their beautiful,
toxic blue lake, they found the water had completely
changed color and was not nearly as inviting.
The lesson here is
just because something looks beautiful,
that doesn't mean you should immediately
expose your entire body to it.