All language subtitles for The UnXplained Special Presentation S01E11 1080p WEB h264-EDITH_track3_[eng]

WILLIAM SHATNER: A vast empire
that mysteriously collapsed.

An ancient metropolis

reclaimed by the jungle.

And an abandoned city that sits

in the middle of the desert.

All over the world,
we're surrounded by the ruins

and artifacts of ancient empires

that were once thriving,
powerful cultures.

What's left behind
offers intriguing clues

about how our ancestors lived.

And it makes you wonder
how an entire civilization

can simply disappear.

As we dig deeper,

what secrets will be uncovered

about mankind's past?

Well...

that is
what we'll try and find out.

♪ ♪

SHATNER:
Explorers John Lloyd Stephens

and Frederick Catherwood mount
an expedition to investigate

reports of mysterious ruins

located in this remote,
largely uncharted region.

After scouting and mapping

miles of dark,
impenetrable jungle, they find

some unusual features
in the dense brush.

Oddly shaped stones,

peculiar carvings,

and strange artifacts
that could only be...

man-made.

It isn't long
before they realize

they've made
an incredible discovery:

the remains of the mysterious

ancient Maya civilization,

deep in the rainforest.

CARL WENDT:
And what was so remarkable
to Stephens and Catherwood

is eventually they found temples
and platforms and pyramids.

There was monumental
architecture and conical mounds

and other building platforms
in the rainforest.

And to look at these cities
in the jungle,

kind of coming out
of the jungle, was...

was just absolutely remarkable.

And it got people's attention.

SHATNER: On their return
to the United States,

Stephens and Catherwood
publish an illustrated book

of their findings,

detailing 44 individual ruins.

Readers are astounded
by the book's

meticulous illustrations,

which portray
a sophisticated ancient society.

And news of the astonishing find

quickly spreads
around the world.

WENDT:
The Maya become more mysterious
as we collect more information.

They have a sophisticated
writing system.

They obviously have a
sophisticated religious system.

And calendar system.

And so the calendar, which
would've been a very useful tool

for the Maya elite and priests
to be able to understand,

say, for example, when there was
gonna be a solar eclipse.

They were ancient astronomers
and architects.

They have social structure

that we're just beginning
to understand,

and their cities are remarkable.

SHATNER:
At its peak,

the Maya civilization stretched
from Guatemala and Belize

to western Honduras
and El Salvador.

Their total population was
estimated to be in the millions,

and concentrated in large
city centers like Copán,

Tikal and Calakmul.

And then, suddenly,
during the ninth century AD,

this advanced society just...
collapsed.

Vast cities, ornate palaces,
towering pyramids,

all of it, completely abandoned,

left to be reclaimed
by the jungle.

But why?

ED BARNHART:
The mystery of why

Maya civilization collapsed
is one

that archeology has been
debating forever.

830 is right about when all
of the cities in the Maya area,

and all over Mesoamerica,
are falling apart.

They drop their tools,
and they walk away.

They're abandoning those cities,
and it's a mystery.

Where did the people go?
Why did they leave?

If you have such
a sophisticated civilization,

how do these things collapse?

What went wrong?

SHATNER:
For decades,
archaeologists have speculated

as to what might have caused
the sudden demise of the Maya.

Dozens of theories--
blaming everything

from drought to disease
to devastating earthquakes--

have been proposed.

Yet, the simple truth is,

no one knows
what really happened.

But a recent study, using
state-of-the-art technology,

might have provided
a significant clue.

An airplane operated
by the University of Houston's

National Center
for Airborne Laser Mapping

flies 2,000 feet
above the thick jungle canopy.

As the plane reaches
its target area,

an advanced scanning technology
called "lidar" is used

to fire laser pulses through
the trees at the ground below.

When the resulting data
is later compiled

into a three-dimensional
rendering of the area,

the scientists are stunned
by what they see.

Once lidar got involved,

we saw the roads leading out
into other city centers.

We saw thousands
upon thousands of houses.

Collectively, all the areas
that they covered

were over 60,000 new buildings
that we didn't see before.

Previously, they thought

that the Maya reached probably
a maximum level

of population
of around five million,

but the estimates now take us

up to at least 15 to 20 million.

SHATNER:
Ever since the rediscovery
of Maya ruins

by Europeans
in the 19th century,

nearly every piece
of data uncovered

about the Maya
raised more and more questions.

But now, after scientists
began using lidar,

they finally started
to find answers,

such as the possible cause

of the Maya
civilization's collapse:

war.

WENDT:
Once we started going out

and recording
and mapping these sites,

we see
defense warfare structures.

This is a remarkable thing,
that we never knew

that these defensive works
were out there,

leading archeologists
to scratch their heads

and basically say, "Oh, my gosh,
the Maya were warlike,

and warfare was very important."

DAVID WHITEHEAD:
We know
there was warfare going on.

They were building all kinds
of defensive structures.

Could that have something to do

with the vanishing
of the Mayans?

BARNHART:
More and more,

as the classic period went on,

monuments became full
of war imagery,

and people taking captives

and people being beheaded.

So we know war was a factor.

If it was just war,

the victors would've
claimed the land,

and the losers
would have beat it.

But that's not the fact.

Everybody left. Why?

SHATNER:
According to the Popol Vuh--

the written history
of the Maya--

they believed that time
was cyclical in nature.

Each cycle lasted
for a fixed number of years,

at which time, a great cataclysm
would wipe the slate clean

so a new world could be born
from the old one's ashes.

So was this the real reason?

Did the Maya abandon
their great cities

and disband their culture simply
because an ancient prophecy

told them when exactly to do it?

BARNHART:
The timing is very interesting.

In 830, a great cycle is ending,

and there was certainly
evidence for them

to believe
that things were going bad.

There were climate problems,

there were resource problems,

there were people fighting.

Were they timing
the leaving of their cities

to the calendar
that they created?

That's a... a big possibility.

SHATNER:
Right or wrong,
the Maya believed

that the end of
their civilization was at hand.

And while that may seem
like a far-fetched notion,

there actually exists
one group of people

that hold similar beliefs:

the descendants of the Maya.

When you talk
to modern Maya people

in the Guatemalan Highlands,

people called daykeepers,
ajq'ij,

they are priests who still

follow the calendar,
and they teach people

that things begin,
and they come to an end.

And that to be in harmony

with the world
you need to know these cycles

and change
before the world changes you.

It's very possible
that, back then,

when all the signs
that the world was going...

a serious wrong direction,

that the Maya civilization
as a whole said,

"These are the signs.
The time is now.

Let's collectively
change ourselves."

SHATNER:
Was the collapse
of the Maya civilization

simply the result
of a self-fulfilling prophecy?

It seems that the truth
about their fate

may be a matter of belief.

Which may also be the case
regarding

an ancient society in Cambodia
that mysteriously abandoned

one of the largest
temple complexes ever built.

SHATNER:
Deep in the northwestern jungles

of this small nation,

tucked between Vietnam
and Thailand,

sits the abandoned ruins
of Angkor Wat,

a massive, ancient complex
of temples.

Experts believe
that Angkor Wat is the largest

religious structure ever built.

STEAVU:
It's just a massive,
impressive sight.

swallowed up by the jungle.

Trees are wrapping
around some of the stones

and sculptures that-that remain,

yet you can still make out
some of the exquisite sculptures

between leaves and branches.

And you can see something
really majestic underneath.

BARNHART:
Angkor Wat is huge.

When you walk up
to its front entrance,

it's a bridge going
across the moat, and then,

a causeway going
to the temples themselves.

And they're so far off
in the distance,

you walk across that bridge
for ten minutes,

and you're still not
at the temple.

SHATNER:
All told,

Angkor Wat encompasses
more than 401 acres

of buildings,
temples and gardens,

and a 700-foot-tall spire sits

at the center of the complex.

Angkor Wat was built
in the 12th century AD

by the Khmer people,

and it was the spiritual center
of their empire.

DOUGHERTY:
It's difficult to explain

just how important
this place was.

In fact, "Angkor Wat" means
"capital city"

or "capital temple,"
or "city temple,"

depending how you translate it.

So, this was not only
a religious center,

it was also a political center,

it was a military center.

There was absolutely
no separation

between religion and daily life.

The temple served
all of these purposes.

And it was home to tens
of thousands of ordinary people

who were farmers, merchants

living in this tremendously
important religious center.

STEAVU:
It was a massive, vibrant city.

The urban landscape extended

far beyond Angkor Wat itself,
in every direction,

for, uh, miles,

so there were anywhere
between about 750,000

to a million people living
around the city of Angkor.

SHATNER:
In the year 1431 AD,

the Khmer people
abandoned Angkor Wat.

For decades,
archaeologists have speculated

as to what caused
the demise of the city.

Numerous theories,
blaming everything

from climate change to invading
armies, have been proposed.

And yet,
no one knows for certain

why nearly a million people

chose to abandon
these magnificent temples.

DOUGHERTY:
The abandonment of Angkor Wat

illustrates to us that something
catastrophic had occurred

within Khmer society.

This incredible place

was still capable of supporting
large numbers of people,

it was still
an important temple,

but it was
almost completely abandoned.

It was just left.

And what that suggests is that

something changed
in the Khmer people.

SHATNER:
Some experts have proposed

that because Angkor Wat was such
an important religious site,

it may have been abandoned
for spiritual reasons.

DOUGHERTY:
Angkor Wat

was the link between
mortal people and the gods.

And it was built
by Suryavarman II,

who fought a series of military
campaigns to unify his people,

brought stability, prosperity.

And Suryavarman II intended

Angkor Wat to be his mausoleum.

STEAVU:
The tomb of Suryavarman II
was intended

to be located
underneath the central tower.

And there's a hole at the top
of the central tower

that lets in a beam of light.

And that beam of light
would have shone directly

onto the tomb,
demonstrating in a way

that Suryavarman was
directly linked to the divine.

DOUGHERTY:
Suryavarman II

clearly intended
to be buried at Angkor Wat.

He would be interred
in the central temple.

But he died on a military
campaign in what is now Vietnam,

and nobody knows
what happened to the body.

SHATNER:
Curiously,
after King Suryavarman died,

and his body was not placed
in its intended tomb,

the living conditions in Angkor
Wat took a turn for the worse.

There were repeated droughts
in the region,

which led to famine,

because there was not
enough water for crops.

But on the other hand,
there were also huge monsoons

that, at times,
would cause major flooding.

Some scholars believe

that these calamities
may have been seen

by the Khmer people as a sign

that their connection
to the gods had been lost,

and that it was time
for them to abandon Angkor Wat.

DOUGHERTY:
The Khmer people

would have remembered
the time of Suryavarman II,

of this golden age
that had existed.

But later,
things weren't as good.

Could it be that the link

between mortals and their god
had been broken?

(birds singing)

STEAVU:
If what made Angkor City great

was the blessings that were
sent down from the gods,

then when things started going
more badly for the city,

people would naturally interpret

that the gods again are
taking away their blessings.

And then that, in turn,
would serve as a cue

for the Khmer people
to also leave behind the city.

BARHART:
All civilizations on the planet,

no matter how big they are,

they eventually fall,
and Angkor was no different.

And the factors were not just
as simple as one thing.

There were a number
of things happening.

In many regards,
the abandonment of Angkor

was just an acknowledgement

that however large and grand
their life was there,

that the gods didn't favor it,
and it was time to end it.

SHATNER:
Did the Khmer people
abandon Angkor Wat

because they believed

that they had fallen
out of favor with the gods?

It's an intriguing theory,

but not all ancient cities
are mysteriously deserted.

Some are frozen in time,

like a town located
near Mount Vesuvius

that was engulfed in
a deadly cloud of volcanic ash.

SHATNER:
At approximately 1:00 p.m.

on a peaceful, late summer day,

this ancient Roman city in
the shadow of Mount Vesuvius

is shaken by
a massive volcanic eruption.

Within minutes,
superheated gas and lava

engulf the city
and its surroundings.

(people screaming)

In an instant,
thousands of people

are buried alive as a city

that was once their home...

suddenly becomes their tomb.

Nearly 2,000 years
after the eruption,

Pompeii is a city
that remains frozen in time.

LAPATIN:
This eruption was

what we call
a pyroclastic eruption,

where clouds of ash and debris

hundreds of degrees hot
came flowing down the mountain,

flash-frying everything
in its path.

And, miraculously,
the heat of this cloud

was enough
to carbonize and preserve,

rather than destroy,
all kinds of information.

We have
well-preserved architecture,

wood and organic materials,
foodstuffs,

human remains,

animal remains that have
been preserved for 2,000 years

beneath this volcanic debris.

SHATNER:
Today,
the excavated ruins of Pompeii

offer archaeologists
and tourists

a breathtaking look
at the doomed ancient city.

Perhaps the most intriguing
discovery found beneath the ash

from Mount Vesuvius's eruption

was an ancient Roman structure
located not far from Pompeii,

known as the Villa dei Papiri.

LAPATIN:
The Villa dei Papiri

was a Roman luxury villa

that was full of sculpture

and marble and bronze.

The villa was discovered
by chance

in 1750 by well-diggers,

who, tunneling about 75 feet
through volcanic debris,

first hit a colored marble floor
with an amazing pattern

made up of bright red
and yellow marbles.

We think this was once
the vacation home

of a Roman senator
of the highest rank

of an old noble family,
named Lucius Calpurnius Piso.

SHATNER:
The volcanic ash
that buried Villa dei Papiri

did not only preserve
the physical structure.

It also entombed a library

that contained more
than 1,800 papyrus scrolls.

These scrolls are
an extraordinary record

of the thoughts and writings
of people who lived

nearly 2,000 years ago.

SEALES:
Those texts were discovered

when the city was excavated,

and some of the artifacts
were first found.

The people who discovered them
didn't know what they were.

They thought that maybe they
were pieces of branches or logs,

because they were rolled up
and carbonized.

Until someone finally realized
these are texts on papyrus.

LAPATIN:
The Villa dei Papiri library
is significant because

it's the only surviving library

from antiquity
with its contents.

There were scrolls found

that date to the third,
second and first century BC,

and the first century AD.

About 300 of them or so
have been un-scrolled,

and they contain
mostly philosophic texts,

some poetry,
some literary criticism,

a little bit of history.

But many of the scrolls
are so tightly bound together

and carbonized
that there's been a moratorium

on attempts to open them.

SHATNER:
Fear of damaging the scrolls
has left many of them

virtually untouched
for over 100 years.

But new technology has presented
a potential opportunity

to read
these mysterious ancient texts.

Scientists in
the Computer Science Department

at the University of Kentucky
have developed a new method,

known as "virtual unwrapping,"

which uses a sophisticated
X-ray machine

to scan the scrolls
without damaging them.

SEALES:
The virtual unwrapping
that we innovated

basically allows
a 360-degree set of views

to be collected from an object

that rotates
in front of an X-ray beam.

This is a real scroll
that's 2,000 years old,

and in cross section,
we can see there's damage,

there are parts
that are missing,

sections that are broken.

Now we're using our software
for the second step,

which is to trace these wraps
all the way through

so that we can build a 3D model
that lets us

flatten that out and then
read the text that's on it.

And once we're done,
we've achieved this image

that's on the left,
which is the final,

completely unwrapped version.

This is a quote from Democritus,

who was an early
Greek philosopher,

and is very well known for
having postulated, with others

that materials
are made of atoms.

I think it's remarkable
that 2,000 years ago,

Greek philosophers were
postulating

what we now know is true
from science.

SHATNER:
Thus far, the team has been able

to digitally scan
two complete scrolls,

and a number of fragments.

They hope that, in the future,
technology will advance

and allow them
to reveal even more.

But what secrets
might be contained

in those 2,000-year-old scrolls?

One exciting possibility
that has been suggested is

that original letters written
by Jesus's apostle Paul

could have been kept within
the library of Villa dei Papiri.

RIC RADER:
The Villa of the Papiri
was entombed

about 40 to 50 years
after the death of Jesus.

At this time, the original
apostles are now out

doing their mission work
in various parts

of the Mediterranean.

So, it's entirely likely
that the Villa of the Papiri

could have a collection
of copies of Paul's letters.

SEALES:
If the letters
from the Apostle Paul circulated

and found its way
into the collection,

such a discovery would represent
the earliest Christian material

that we have,
almost dating back

to the time of Christ
and the disciples.

Being able
to use these techniques

to understand history
in a way that's almost forensic

is gonna bring
surprising things forward,

and we're gonna be revealing
more secrets

than we'd ever imagined before.

Are there even greater secrets
contained

within the papyrus scrolls
of Pompeii?

Hopefully, archaeologists
will soon find out.

But some mysteries of ancient
civilizations are not buried

beneath volcanic ash
but rather

hiding in plain sight.

For instance,
there's a vast pyramid mound,

constructed more than
a thousand years ago,

that is located in the heartland
of the United States.

SHATNER: In the heart
of the downtown district

stands the Wainwright Building.

Built in 1891,
this office building is one

of the world's
first modern skyscrapers.

But as it turns out, there is
a similarly-sized structure

in this region
that is much, much older.

Just ten miles east of the city
stands the ruins

of an ancient,
man-made pyramid mound

that was built centuries ago,

and is as tall
as a ten-story building.

BILL ISEMINGER:
This is

the largest
prehistoric earthwork

in the western hemisphere,

the largest totally
earthen mound built

by ancient people
in North or South America.

Its base actually is bigger
than the great pyramid in Egypt,

and it stands 100 feet high.

And it was built with about
22 million cubic feet of dirt

that had to be carried
in baskets

on people's backs and deposited.

SHATNER:
The fact that the ruins

of a man-made pyramid sit
in the middle

of the United States might
come as a surprise, for some.

And yet, this monumental
earthen mound is merely one

of more than a hundred
similar structures

that have been discovered
in this area.

They are all part of a sprawling
ancient city named...

Cahokia.

COLLINS:
Cahokia

is arguably the most important

of the ancient cities
of North America.

Constructed approximately
between 700 and 1350 AD,

it was an incredible metropolis.

We have this idea
of the first peoples

as being hunter-gatherers,

and riding around
on horses all the time,

and that's simply
the wrong impression.

They were
an incredibly technologically

sophisticated society.

ISEMINGER:
We don't know
what this place was called

or what-- the language
that people spoke here.

The name Cahokia comes
from a later group

of American Indians
that moved into this area

in the 1600s from further north
around the Great Lakes.

They were here, but they did not
build the mounds.

They just later used it
as part of their settlement.

We often use the term "city"
when we talk about Cahokia

because of its magnitude.

It covered
nearly six square miles

or about 4,000 acres.

During its peak,
between 1050 and 1150 AD,

there were probably,
you know, 40,000-50,000 people

living within this region.

It would be larger
than London was at that time.

And yet, 200 years later,

by 1350 AD,

the whole place
had been abandoned.

And indeed, there is a mystery

of exactly
what took place there.

SHATNER:
But if Cahokia was such
a thriving metropolis,

then it begs the question:

how did this civilization
come to an end?

It's a mystery
that has driven archaeologists

to scour Cahokia's ruins
in search of an answer.

There are a number of hypotheses
about the decline of Cahokia.

And one involves evidence
of a defensive wall

that was built
around the center of Cahokia.

So that indicates that they had
conflicts and warfare.

And there's been
suggestions that maybe,

with the crowded conditions
here, perhaps there was

increases in, in disease.

SHATNER:
Did the threat of warfare
or poor living conditions

cause the inhabitants of Cahokia
to abandon this thriving city?

It's hard to say.

But in recent years,

another theory has emerged.

One that suggests
there may have been

a more sinister reason
behind Cahokia's demise.

So one of the ideas
that's been put forward is

that something quite dark
took place there,

and this is why
there's little evidence

in the oral tradition
or the folklore of this area.

And this could be ultimately
why the site was abandoned.

ISEMINGER:
Back in the late '60s
and early '70s,

there was an excavation

at a small mound here
on the site called Mound 72.

As we dug further
into the mound,

there was a burial pit
about five feet deep.

And at the bottom of that,
they found 53

mostly young women,
all buried at the same time,

laid out in two rows
and piled in there two deep.

Next to them were four men

with their heads
and their hands cut off,

apparently in some ritual.

COLLINS:
The burials that

came out of Mound 72

quite clearly showed evidence
of mass sacrifice.

And we have to ask ourselves

whether this would have had
any kind of impact

upon the society
as a whole at Cahokia.

SHATNER:
Did the vast majority
of Cahokia's inhabitants

abandon their city

because its leaders were
engaging in the practice

of human sacrifice?

And if so,
then where did they go?

Is this tragedy
enough to explain

why there is no written record

that this civilization
ever existed?

For now, experts remain
collectively baffled

and worry that we may
never know for sure.

We really must question,
you know,

what really happened because

it could have been something
much more mysterious

that we just don't know about.

SHATNER:
While we may never know
the true fate

of the inhabitants of Cahokia,

it's quite remarkable that
parts of this vast complex

can still be seen today.

But not all ancient ruins

are hiding in plain sight.

There's a city,
located in the Arabian desert,

that was not merely
abandoned

but rather
deliberately concealed.

SHATNER:
Swiss explorer and geographer

Johann Ludwig Burckhardt sets
off on an incredible journey

across the desert to uncover
the secrets of the Middle East.

Johann Ludwig Burckhardt was

quite an extraordinary
character.

Um, he traveled throughout
Syria, Jordan, Palestine,

and eventually into Egypt.

He also practiced
the Islamic faith.

And the reason for this was that

he didn't want to be seen

as a Western treasure hunter.

SHATNER:
During his travels,
Burckhardt heard rumors

of a mysterious ancient city
known as Petra

that was hidden somewhere
in the deserts of Jordan.

For centuries,
the exact location of Petra

was kept secret from foreigners.

But Johann Burckhardt
was determined to see Petra

with his own eyes,

and so he hatched a wild plan.

PARADISE:
The area had always
shown conflict,

it had always shown
a certain amount of hostility

to European visitors.

And so Burckhardt spent months
in the region,

learning the local dialect
of Arabic,

and then perfected
a bedouin outfit

to look like a local,
or something close.

The disguise was needed
to get him in the door.

SHATNER:
After spending months
following clues

in search of the city,

Burckhardt traveled through
a dark, narrow desert canyon,

and to his astonishment,

stumbled upon
the stunning ruins of Petra,

which were even more impressive
than he had imagined.

Burckhardt was the first
European to lay eyes on Petra

in more than 500 years, and
his vivid account of the city

made headlines
around the world.

Suddenly, the world reads
about Petra.

The entrance into Petra

is this magnificent
carved structure

about 140 feet high.

And it was carved, it was
hewn directly out of the rock.

And that's the beginning.

Petra was a large, large city
of 30,000 to 50,000 people

that was thriving between

about 500 BC and about 500 AD.

It had a city center,
it had a main street,

it had everything you would
think of, even to this day,

that a large city would have.

The builders of Petra
were the Nabataeans.

They were a culture
in their own right

who adopted
the art and architecture

of the Greek Hellenic world,

the Greco-Roman world,

but also had influences
from Assyria

in what is today Iraq.

And they blended all
of this together to create

the incredible
carved architecture

that you see at Petra.

SHATNER:
The more than 800 carved
structures at Petra

are so iconic that in 2007,
the site was named one of

the New Seven Wonders
of the World.

Ever since Petra was revealed
in 1812,

historians have wondered

what could have caused
the collapse

of such a prosperous city?

For decades,
it was thought that shifting

trade routes were responsible,

but research conducted by
archaeologist Thomas Paradise

has revealed new information
regarding the downfall of Petra.

We're really fortunate
that we keep

putting pieces
of the puzzle together.

Using archaeological excavation,

using GIS and laser technology,

we're starting
to put these pieces together

to understand Petra.

New research is indicating
that a large flood hit

in the fifth century
that wiped out the downtown

for at least a year or so.

The city rebuilds
after that flood,

but it marks the beginning of
the decline from its golden age.

SHATNER:
The re-discovery of Petra
has revealed

that the city was important,
not just historically,

but also spiritually.

Because, as it turns out,

this ancient city has
a connection to the Bible.

PARADISE:
Up above Petra--

and it's visible
from most parts of Petra--

is a mountain called
Jebel Haroun.

Jebel Haroun means
the Mountain of Aaron.

And we do know legend says

that's where Moses's brother
Aaron is buried,

below a large tomb
on the top of the mountain.

The keeper of the holy site
at Jebel Haroun...

over the years,
I-I came to know his family.

So, he invited us up there
to go into the building itself,

and then to climb
into the tomb.

That gets you excited
because you realize you're part

of a tradition from
3,000 years of pilgrimage.

Petra's been called
the Lost City of Stone because

here we see a city
of 30,000 to 50,000 people

that slowly fades from
the history books over time.

And what we're going
to find out about Petra

in the future
is probably more incredible

than what we already have
uncovered.

SHATNER:
The re-discovery of Petra
is an extraordinary find

of both spiritual and
archaeological significance,

and one that rewrites
the history books.

But sometimes,
the most remarkable secrets

about ancient civilizations
can be found

by studying not only the ruins

but rather the DNA of the people
who built them.

SHATNER;
Here, on the vast green
pasture of Salisbury Plain,

stands perhaps the most storied
wonder of the ancient world:

Stonehenge.

First constructed
around 3100 BC,

these imposing sarsen and
bluestone monoliths were rebuilt

and repositioned
a number of times

over the next 1500 years,

eventually settling into
the current configuration.

But today, almost 5,000 years
after its creation,

Stonehenge's original purpose

remains shrouded in mystery.

TIMOTHY DARVILL:
Stonehenge is
a complicated monument.

It's a very long-lived monument.

We're always changing

our interpretations
of Stonehenge.

And this is
in large measure because

these societies don't
seem to have had writing.

They haven't
written anything down

that's come down to us,
at least.

So, we're having to piece
together our understanding

of the monument
from what we have

in the archaeological record
in the monument itself.

SHATNER:
For centuries,
researchers assumed that

the ancient people
who constructed Stonehenge

were native
to the British Isles.

That could be changing.

Because thanks to
modern genetic technology,

researchers have been able to
conduct DNA testing

on Stone Age skeletons
that were recovered

in the area around Stonehenge.

And the results suggested
that Stonehenge's builders

weren't native
to ancient Britain at all.

They may have arrived from much,
much farther away.

COLLINS:
It was generally thought

that Stonehenge must have been
built by the local people.

But new DNA evidence suggests

that the builders
of Stonehenge had come

from distant Anatolia,

modern-day Turkey.

NEWMAN:
DNA analysis that shows
this migration

from Turkey to Ancient Britain
is very, very interesting.

Because what we're finding here

is this direct connection
over a very long period,

starting with sites
such as Göbekli Tepe,

which was in Southeast Turkey.

Then we have similar stone
structures, like stone circles

or stone avenues in Portugal,
along the Iberian Coast.

Then we have the sites
in Brittany, France,

which again date
to this very early phase.

And then we start seeing
the megalithic constructions

of ancient Britain.

So, this DNA analysis shows that

they were bringing
this megalithic knowledge.

And this has now been
proved through DNA research

from Turkey, through Europe,

into ancient Britain.

SHATNER:
Is it possible that Stonehenge
was constructed

by the same ancient people
from Turkey

that built other massive stone
monuments all over Europe,

as newly discovered
DNA evidence suggests?

It's one of many
intriguing theories

about ancient engineering
that has been brought to light

by modern technology.

New technologies are
certainly gonna open up

a whole series of new questions.

And it's going to answer
a few things

that we didn't know
too much about.

So, there's still a lot of work
to be done in figuring out

some of the secrets
of ancient times.

I don't know how they moved
such large stones

those great distances,
or why they did it.

Why, particularly,
was that the location

for the stones to be extracted,

and this the location
to actually build them?

It doesn't make sense
to me as an engineer.

I would always want
to move those stones

the shortest possible distance

to the site
that I'm gonna build from.

We've wondered since
the day we discovered it

how they did it,
and we still don't know.

Whether it's sprawling cities
that were suddenly abandoned,

curious artifacts that may hold
clues about the past,

or even the physical
remains of our ancestors,

human history has left
behind fascinating mysteries

that we're still trying
to understand.

Perhaps one day
modern technology will shed

new light on
ancient civilizations,

but until then,
their secrets will remain...

...unexplained.

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