Original subtitles

Angkor, capital of the Khmer Empire.

The largest city in the world in the 13th century.

Angkor, the abandoned city,

whose ruins fascinate visitors from all over the world.

Rediscovered in the 19th century by French explorers,

its remains are evidence

of a prosperous and prestigious civilization,

eventually reclaimed by nature.

Why did this civilization disappear?

That's the question scientists from all over the world

are hoping to answer today.

If a place like this was abandoned,

apparently fairly quickly,

there must have been some very good reasons.

The abandonment of Angkor

cannot be put down to another whim of the king.

It wasn't as though he didn't like the climate

and would rather have had a change.

Angkor was in a sense the Khmer's eternal city,

and it has remained so.

No texts mention the end of Angkor,

apart from one passage in the chronicles of Ayutthaya,

a neighboring kingdom and enemy of the Khmer empire.

Its inhabitants, the Siamese,

claimed to have defeated the king of Angkor's army.

After which, the sovereign and his court

hurriedly left the capital in 1431.

If it turned out to be true,

this event would be of major historical importance,

as the Khmer empire had dominated the region

for several centuries.

Its prestige was considerable, according to the accounts

of a Chinese diplomat, Zhou Daguan, who was received

at the court of the king of the Khmers in 1296.

Australian archaeologists have used his accounts

to produce these images.

An accurate representation

of what the city of Angkor looked like in its heyday.

The first striking thing is the sheer number of vast temples

and their rich decoration.

They're entirely covered in bronze and gold.

This is Angkor Wat, the largest of all the temples,

which was built at the beginning of the 12th century.

This is Phnom Bakheng,

one of the first sanctuaries

built at the beginning of the 10th century.

At its height, Angkor was a vast city,

covering several hundred square kilometers.

Today, Christophe Pottier, an archaeologist

with the French School of Asian Studies,

is on his way to Beng Mealea, an outlying temple.

It is one of the many vast temples

that once dotted the plain of Angkor.

In the investigation into the kingdom's demise,

this place is of particular importance.

Almost completely in ruins,

this monument has never been restored.

It therefore constitutes the best possible evidence

about the circumstances of its destruction.

Was this monument smashed to pieces by man

or by the forces of nature?

This is the question Christophe Pottier

has been trying to answer for years.

The French archaeologist

is part of an international research group

trying to solve the mystery of the decline of Angkor.

Beng Mealea is perhaps the last place

to still give us a fair idea of what the first explorers

must have felt when they discovered Angkor

in the late 19th century.

These gigantic ruins,

these piles of stones covered in lichen and leaves.

A really spectacular contrast between man's achievements

and the vegetation that reasserted its dominance

over a civilization buried in the jungle.

This cone of blocks is just the central sanctuary

of a temple that is Angkor Wat's twin.

It has the same dimensions,

it was built in the same period, the 12th century,

so it has the same quality of workmanship,

the same series of galleries, terraces, and towers.

Is there any archaeological evidence

of the Khmer's defeat by the Siamese in 1431?

The archaeologist studied the ruins of the Beng Mealea

temple in order to find, for example,

signs of a deliberate destruction.

But there were none.

The temple was evidently emptied of its contents,

but the temple itself was in almost perfect condition.

The encroaching vegetation subsequently destroyed it.

The central sanctuary must have been looted,

but we don't know exactly when,

maybe at a much later period.

Anyway, finding temples in this sort of condition

is a clear indication

that a major battle did not take place,

and that the temples were not set alight,

as has been suggested by stories of border conflicts

with the nascent kingdoms of that era.

If Angkor's disappearance

cannot be explained by a devastating war,

what else could have caused its demise?

To answer this question, the scientists first looked

to the achievements of this civilization,

which might later have led to its decline.

The farming of an extensive area.

A low-density but dispersed urban complex.

And a flourishing trade center.

Angkor was a key trade hub between India and China,

and the rice bowl of the region.

But the city's linchpin was its water management network.

Hundreds of kilometers of canals and channels,

which obviously required constant maintenance.

Researchers are taking a close interest in it.

Christophe Pottier is on his way to Phnom Kulen mountain,

the birthplace of the Khmer empire.

Quite simply because this is where the river,

which runs along the plain of Angkor, takes its source.

In the dry season, it doesn't look like much.

But when the monsoon rains come,

it turns into a raging torrent.

The Khmers have always venerated it,

and have carved lingas, the symbolic form of Shiva,

on its bed and banks.

The rectangular frames around them are yoni,

the embodiment of female energy.

The sandstone bed has been carved

with hundreds of small lingas, each with its own yoni,

and the river naturally ripples them.

And it was this sacred river

that flowed across the plain of Angkor

and into the canals, channels,

barays, or reservoirs, and rice fields,

which fed the Angkorian civilization.

For the Khmer, but also for all civilizations,

it's obviously the source of life.

It's all the more important here

because this is a tropical monsoon climate.

Half the year, there's too much water.

You have to protect yourself from it as quickly as possible.

And the other half of the year, there isn't a drop.

It's extremely dry,

so you have to store the water somehow.

The Khmer civilization's mastery of water

is both its strong point, and its Achilles' heel.

This place has strong symbolic significance.

That's why the empire's first sovereign

decided to establish his capital here.

Archaeologist Jean Baptise Chevance

is the world's leading expert on the Phnom Kulen mountain.

He is on the trail of this lost city,

but for the time being he has only found scant remains,

roof tiles, and a few foundation stones.

However, a few kilometers away,

several holy buildings are still intact.

The mountain's use as a religious site was interrupted.

Jean Baptise Chevance has surveyed it.

He has restored and studied this temple,

one of the oldest on the sacred mountain.

Its presence is closely connected

to the water management network,

which starts high up on the Phnom Kulen mountain

with this astonishing waterway hollowed out of the rock.

It's a highly original feature.

This channel is several hundred meters long,

and a section of it was hollowed out of the sandstone,

straight out of the mountain,

which is an amazing feat.

You can see the tool marks here,

some of which are diagonal and at regular intervals.

You have these bore marks.

They did not let the landscape get in their way.

In other words, even if there was a huge natural obstacle

such as this mountain, they kept on going,

and with considerable means,

They broke this block of sandstone

in order to direct the water wherever they wanted.

Water management requires collective effort, large-scale coordination,

and efficient and effective organization,

so the kingdom's foundations had to be found in this system.

Religion was also an integral part of the waterway system.

The sources are sacred, and managing their flow

was probably a spiritual duty for all Khmers.

Water therefore holds the key

to understanding the kingdom and its capital.

A Chinese diplomat in Angkor, Zhou Daguan,

gives us an idea of the cohesiveness of the Khmer people.

He describes in particular New Year,

when spectacular festivities were held in front of the royal palace.

The year is 1296.

There is nothing to suggest that in little over a century,

the Khmer's capital will have ceased to exist.

Christophe Pottier is searching for the city's weak point,

a weakness that might have proved fatal

and prompted its inhabitants to leave.

The archaeologist believes he has identified it

by closely observing the region's landscape.

He's managed to find the trace

of the vanished city's water management system.

These hundreds of canals and reservoirs

and been filled in over the centuries,

and covered over by vegetation.

But in the past 20 years,

the archaeologist has learned to read

the topography of the plain of Angkor,

and now knows the main lines.

Its development always followed an identical pattern.

In the center is the temple,

which symbolizes the celestial mountain

surrounded by moats and pools.

The overview map, produced by Christophe Pottier,

reveals a grid network covering over 3000 square kilometers.

That's an area almost as large as New York today.

Those are the lines of the great canal,

which ran from the temple of Bakong

all the way down to the lake in the distance.

And you can see to what extent

the Khmers purposely modified their environment.

The water network

was made up of over 200 large canals.

Some were more than 20 kilometers long.

They were used in particular as communication routes.

Here is one of the Khmer capital's most impressive

water management features, its reservoirs.

There barays can hold over 50 million cubic meters of water.

They were of strategic importance to the Khmers.

This is one of the largest, the West Baray.

Eight kilometers long, two kilometers across,

the far shore is two kilometers away.

It's a man-made rectangular reservoir.

Its waters are contained by huge banks

that are over ten meters high

and 150 meters wide at the base.

The baray was a key element for security

for rice farming in the area.

As well as this, its vast holding capacity

meant it was also possible to distribute water

to fields to the north, and to dispose fairly rapidly

of water into the lake.

So it is a feature that probably had several purposes,

including supplying water for domestic use

to the surrounding population in the dry season.

Construction of the West Baray

began in the 11th century,

but this area had been inhabited previously.

The reservoir actually submerged an ancient city

that Christophe Pottier is now excavating.

It was built around this pyramid-shaped temple

known as the Akyum, probably dating from the 7th century.

Flexibility was part of the Khmer culture.

The kingdom of Angkor moved its capital several times.

Christophe Pottier has pieced together

their phases of construction.

Each of these capitals had its central temple,

around which the Khmers laid out their city.

The temple of Akyum was erected in the 8th century.

Then the Bakong,

followed a hundred or so years later by Phnom Bakeng.

Then, in the 10th century, Pre Rup.

Takeo marked the foundation

of the first capital of the 11th century.

Then came Baphuon,

and in the 12th century, the world-famous Angkor Wat.

And finally, the kingdom's last capital city,

Angkor Thom, and its temple with a thousand faces.

So in 700 years of existence,

there were at least seven different capitals.

This is how the Khmers populated the plain of Angkor.

At its peak, the seat of the kingdom

had one million inhabitants.

Its size and complexity made it powerful and prestigious.

But did this become a handicap over time?

This is the town of Siem Reap,

a few kilometers from the temples.

Hundreds of statues and architectural elements,

the results of a century of excavations,

are stored here at the Angkor conservation office.

Their artistic value is limitless.

But above all they constitute extremely important

archaeological evidence.

Dominique Soutif and Julia Esteve, two French scientists,

are studying vital clues here

in the investigation into the decline of Angkor.

A series of inscriptions dating from the 12th century.

In Cambodia, about 1300 inscriptions have been found.

400 of which are conserved here.

Actually, this is just a small part

of the literature of Cambodia,

because all the rest were written on hutan palm leaves.

These have obviously disappeared.

They weren't conserved. They rotted.

And today, all that we have left

in the way of written archives

are these texts carved in stone.

A stele has caught the scientists' attention.

It was discovered by the East Baray,

one of Angkor's largest reservoirs.

According to these inscriptions,

priests were in charge of this huge

water management structure that once contained

millions of cubic meters of water.

A reservoir whose site is now occupied by a rice field.

Who were these priests?

Did they live near the baray?

This is what Julia Esteve and Dominique Soutif

are trying to find out.

The two archaeologists have unearthed religious foundations

which the Khmers called akrama.

They were stone buildings covered with light materials.

The round holes you can see here in the ground

housed wooden posts that supported

the tiled timber frame roof.

They were places of worship,

places where people could come to pray,

places of spiritual retreat, places of refuge,

and also places of learning.

They were all that at once.

An examination of the ceramics has confirmed

that the first akrama were established in the 9th century.

Place under the patronage of a deity,

these akrama had a considerable share of power in Angkor.

They were responsible in particular

for the water management system.

This system was perfected by one of the greatest monarchs

in Angkor's history.

1181, Jayavarman VII came to the throne.

Angkor's last great stone monuments

were erected during his reign.

Unlike previous capitals, this new one had defensive walls.

In its center stood the mountain temple of Bayon,

whose most distinctive feature

is its many Buddha-like faces.

The king's face is a picture of wisdom,

but Jayavarman VII was first and foremost a feared warlord.

The walls of his temple depict his victories

against the armies of Champa,

a neighboring kingdom that occupied Angkor for four years.

The king drove them out of his capital,

and then embarked on a massive program

of building in public works.

In under ten years he restored his predecessors' cities,

built his own city, and also erected

two large religious buildings

directly inspired by the akrama.

The Ta Prohm, built in honor of his mother,

a 70 hectare temple complex.

Unlike previous temples,

this complex was not dedicated to one deity,

but to hundreds of gods and goddesses.

Its purpose was to bring together as many gods as possible,

just like Preah Khan,

a temple built in honor of Jayavarman VII's father,

a 56 hectare complex.

More than just temples,

they were genuine towns whose wealth and power

were unequaled in the history of the kingdom.

The archaeologists became convinced of this

after examining other inscriptions

of the Angkor conservation office.

This two meter-high stele

was found in the temple of Preah Khan.

The inscription in the stone is in very poor condition,

so to read it, a stone rubbing is created.

It gives very precise information

about the organization of the temple,

and its place in the society of the time.

How many people were attached to it?

How did this institution function?

The stele will enable the archaeologists

to answer these questions.

Silk paper is applied to the stone.

The then stele is inked to produce a negative imprint.

The inscriptions are now perfectly legible.

And what they reveal about the heyday of Angkor

is particularly spectacular.

Much more than places of worship,

the temples were actually tools for controlling the masses.

Dominique Soutif has been studying these texts

for several years, and he has discovered

that in the day of Jayavarman VII,

the temples became ten times more powerful and wealthy.

The king and the owners of villages

piously gave 5,324 villages,

totaling 97,840 men and women,

including 444 chiefs, 4606 male servants, cooks, and others,

2298 female servants, including 1000 dancers.

47,436 individuals offering the oblation.

Here we have huge quantities of gold, silver, copper,

bronze, gold bowls, pewter, lead, iron,

almost 100,000 gems, including rubies, about 170,000 pearls.

So they had a considerable amount of wealth

if you consider that, in the Angkor area alone,

there were also the temples of Ta Prohm,

Banteay Kdei, and Ta Som.

These religious foundations constituted

a real economic machine,

a very very powerful economic player

which had huge resources, and really ran the region.

At the dawn of the 13th century,

the king completed his plan.

The temples of Angkor absorbed

all the labor power of the Khmer people.

250,000 people worked

for the kingdom's great religious institutions.

The society was booming.

Never had it seemed so powerful,

and yet it was far more vulnerable than it appeared.

Siem Reap Airport.

Today the most sophisticated technology

will advance the investigation into the decline of Angkor.

Damian Evans and Chris Cromarty

are part of the international research group

that is trying to solve the mystery

of why the city was abandoned.

Where we're flying in today is just through here.

Bakong, you'll see, is an amazing big pyramid temple there.

This is a first.

A light detection and ranging system, or LIDAR,

which will give them a totally new view of Angkor.

Never before have so many international teams

and so many archaeologists come together

and acquired such precise data over such a huge area.

Some of those teams are quite heavily focused on the temples

and my personal focus is really on the landscape around,

so the real value of the data is it gives you

incredibly detailed three-dimensional models,

not only of the temples, which everyone studies

and everyone knows very well,

but also the context of those monuments.

Everything is based on GPS.

We have a GPS unit on the tail over here,

and then we have in this scanner here, we have a laser.

The plan is every six seconds

it will take a still photo with this

and the laser will fire at 150,000 times per second,

and that gives us all of our ground returns,

elevational data.

Six hours a day, Damian, Chris, and their team

will fly in a grid over the plain of Angkor.

Thanks to the LIDAR,

they will collect a maximum amount of data.

The site surveyed will be centimeter-accurate.

The topography of this vast area

promises to provide invaluable information

to the scientists.

The LIDAR sweeps the ground with light pulses.

It can see through vegetation

and measure subtle variations in surface topography.

The aim is to identify traces of the urban fabric of Angkor,

and eventually create a three-dimensional map

of the vanished city.

The mission will last five days.

To understand the importance and challenges of this study,

we have to follow Damian Evans.

He is heading to the area

immediately around Angkor Wat temple complex.

Six centuries have gone by since Angkor was abandoned,

and what was once a city with housing, communication routes,

and administrative buildings,

has now been covered by dense tropical forest.

Damian Evans is right in the center of the vanished city.

You have to imagine that during the Angkor period,

this was nothing like what we see today,

so instead of this forest here,

there would have been hundreds and hundreds

of wooden structures.

Huge houses, administrative buildings,

residential quarters, and so on.

This big temple that's in the forest behind us

would have had thousands and thousands of people

devoted to maintaining that temple

and to its everyday functioning.

Those people would have lived here.

And all around us in the surface of the landscape,

these little mounds and ditches and so on

are basically all that remains of that city

that was once here where there is now forest.

You simply have to bend down here

and look carefully to find traces of Angkor's inhabitants.

Everywhere we look around us on the landscape

we see traces of their existence.

Traces of their existence in the topography,

in the mounds, the surface of the landscape,

but also in physical evidence.

Very small material remains like this shard of ceramic here.

It shows us evidence that this place was occupied

during the Angkorian period.

That's the base of a statue.

That's where it would have sat

on some kind of pedestal,

and the feet of the figure remains,

as well as part of its clothing,

the figure's central clothing coming down here

The archaeologists have a hard time reading

what is in the forest without the aid of new technology.

The advantage of such technology is that

it can also cover Angkor's vast territory.

A city that has much in common with the urban areas of today

except that instead of highways, it had a water network.

The researchers already had a general knowledge of it,

but with the LIDAR, they will discover all of its branches.

Between each of the vanished cities' great temples,

they formed a complex network,

which was extremely difficult to maintain.

Damian Evans has a feeling

that Angkor's fate is related to this.

He is convinced that the Khmer ended up

losing their mastery of water.

It is possible a major problem

in the water management system

plunged Angkor into difficulty and caused its decline.

On the surface of things, a lot of the technology

doesn't seem all that complicated.

All that they're doing basically is creating mounds of earth

and digging holes in the ground,

and using the dirt from those holes to create

canal walls and barriers and so on.

The technology is in some ways quite simple,

but really if you look at the functioning

and the operation of the system,

it's an incredibly complex bit of engineering.

The levels of the water and of the canals

have to be incredibly precise.

It's so flat around here that it presents

a real engineering challenge that they were able

to deal with more or less successfully

over the course of many many centuries,

although they faced constant problems, constant challenges,

things constantly breaking down,

which is why you see this accumulation

of so many different parts of this system in the same area.

The big question for us really is,

did the water management system break down

and in some way help to cause the decline of Angkor,

or was it something that came afterwards

and was a result of the decline of Angkor?

That's what we're trying to figure out

in terms of the water management system.

The data collected in the past five days

will be shared with scientists all over the world

who are interested in the history of Angkor

and the reasons for its decline.

Whether they are working on the architecture of the temples,

the city's urban fabric, or its water management system,

they will have an almost inexhaustible supply of data.

With the mission over, Damian and his colleague Chris

meet in the office of the University of Sydney in Siem Reap.

For the first time, they are going to see the 3D images

that the LIDAR will enable them

to produce in great quantities.

That's the enclosure wall just behind it.

Really, the amazing thing about this is the ability

to look at different scales of information.

You can look at the landscape scale,

the overall big picture of Angkor,

the structure of urban space and so on,

and zoom in right down to the very smallest level of detail,

looking at centimeter level difference in terrain

And really to understand what happened here,

you need precise information at these different scales

from the largest scale down to incredibly small detail.

That's what we're looking at really for the first time here.

As an estimate, how many points in total

do you think we acquired over all of the coverage areas?

I would think probably close to two or three billion.

That's a lot of data.

These data will be extremely useful.

Not only for discovering ancient water management features

like canals and so on, which we can profile,

but also for modeling how they functioned.

We can work out basically how water used to flow

throughout the temples, how changes in the system were made

and how that affected the flow of water and so on,

which are of course very important historical questions.

The scientific interpretation

and the modeling of Angkor's topography

will be especially complex.

No firm conclusions can be expected

before several months, or even several years,

and these conclusions will mean more onsite checks.

Only then will it be possible to understand

when and how the water management system

broke down for good.

But another scientist could answer these crucial questions

without waiting for the LIDAR's results.

He is collecting extremely valuable data

in the region of Ratanakiri in the northeast of Cambodia.

Dan Penny is studying climate change,

and is also part of the international research group

investigating the reasons for Angkor's decline.

Dan is currently looking at lakes

where there is no evidence of human presence.

The significance of lakes like this

is because they're very deep,

and because they're very deep

they preserve a unique record of climate,

but also a unique record of the ecology of this area.

That would be the plants and the animals

that live in the lake, and the plants

that exist around the lake are all sensitive to climate.

All of those plants and animals leave a signature

in the sediment of this lake.

So if you can take a sample of that sediment

and bring it to the surface, you can go back in time

looking at changes in the ecology of the lake,

and changes in the ecology of the forest.

From that you can read and understand

past variability in climate.

Dan Penny took several samples

from this lake in Ratanakiri,

so collecting a record of the region's climate.

Then, at the University of Sydney,

he analyzed all the organic particles

contained in these samples.

This enabled him to identify the animal and plant species

living in this environment at the time of Angkor's decline.

These species proved the existence of a major climate change

at this crucial period in the Khmer empire's history

from 1330.

We see not only long periods of drought,

but switches to very wet monsoons very abruptly.

You would have maybe five, six, seven years of drought

and then one huge monsoon.

It seems to have been in those events

which were the most damaging to the system at Angkor,

and which fatally compromised its ability

to store and manage water.

This appears to be even truer when one considers

that at the same time, the plain of Angkor

was suffering from severe deforestation.

Initially in the 7th century the vast tropical forest

covered most of the region.

But over time the Khmers cleared the land,

planted fields of rice, installed an elaborate

water management system, and built settlements.

So the increasingly heavy rains had catastrophic effects.

With no trees to anchor the soil with their roots,

it was washed away.

The large reservoirs and the waterways

suddenly saw the volume of water rise

and its flow accelerate.

The water carried an increasing amount of residue.

This probably accumulated

and filled the main arteries of the water network.

In the space of a few years,

the barays, Angkor's largest reservoirs,

were totally or partially blocked.

The question is at what point

did this situation become irreversible?

Christophe Pottier has found an astonishing clue.

A bridge in the center of the ancient city of Angkor.

A bridge that has lost the river it once straddled.

A bridge used to cross this river.

These arches prove it.

And now this river flows six meters lower down.

So in about six centuries, it has gone down six meters.

There is an obvious problem.

The river has scoured out its bed.

On the piers of this bridge,

there are decorated blocks.

And for an expert of Khmer art like Christophe Pottier,

it's easy to recognize the Jayavarman VII style.

This means it is possible to date the bridge

and determine when the river began to shift.

This bridge was built with architectural elements

from other buildings, which are very easy to spot.

You can see pieces of pediments, parts of statues,

bits of devitas of the asparas,

and these pieces come from a temple, the style proves it,

dates at least from Jayavarman VII's time,

so from the late 12th to early 13th century.

This means the bridge cannot be earlier.

So in fact, it was already the beginning of the end.

And at the beginning of the end of Angkor,

the water was still flowing where I'm standing now.

At the time of climate change,

when deforestation has reached a point of no return,

the river scoured out its bed.

It then went around the bridge, which ended up obscuring it.

Not only did the river move six meters

to the left of the bridge, it also dropped by six meters.

This means that climate change and deforestation

had devastating effects.

And this occurred well after the death of Jayavarman VII.

Deforestation, major changes upstream,

could have caused increased erosion, and consequently,

when vast quantities of water arrive very quickly,

as they do in the rainy season,

this could have led to severe flooding.

Maybe there was a combination of reasons.

But unfortunately, it's very difficult

to know exactly what they were.

But this here is proof that a massive problem occurred.

At the beginning of the 14th century,

Angkor's water management structures

encountered huge problems.

After a time, they may have stopped working altogether.

The price that society had to pay to repair them

was probably exorbitant.

The Khmers had to make

the most painful decision in their existence.

Fight or flee?

For Christophe Pottier, this small temple

deep in the forest of Angkor Thom,

the kingdom's last capital,

is an important key for understanding

the period of the Khmer civilization's decline.

At the top of the steps leading to the sanctuary,

there is an inscription.

It says that this temple was offered

to a Hindu divinity by an important person.

There is nothing extraordinary about this.

Donations of this type were common in the Khmer kingdom.

However, this inscription is historic.

It marks the end of a religion, Brahmanism,

and that of a social order.

This inscription allows us

to precisely date the foundation, 1295.

Mangalartha, who was an important member of the court,

founded the sanctuary, which he dedicated to Vishnu

and made the donations.

Land, people, servants, neccessary for the running

and upkeep of this foundation.

So it was a typical foundation.

But this inscription is in Sanskrit,

and it's one of the last inscriptions

in Sanskrit to be found in Angkor.

Or, at least it's the last that allows us

to date a monument built of sandstone.

Inscriptions in Sanskrit become increasingly rare,

and eventually disappear altogether.

The monuments themselves, stone monuments,

an absence of inscriptions means its impossible

to date them after this time,

and they seem to have disappeared too.

In any case, no other monuments of this type

appear to have been built.

Even though building more continued,

there were no more new small sanctuaries

like this in the large royal foundations.

1308, another stele,

another text in the Angkor region

mentioning a royal donation to a monastery.

This time it is not written in Sanskrit,

the language of scholars, but in Pali,

the language of the new official religion,

Theravada Buddhism.

Unlike Hinduism,

this religion emphasized the individual over the group.

Each person much reach enlightenment on their own,

and was probably less hierarchical.

In any case, monumental structures were no longer built.

Everything was ephemeral.

Wooden pagodas and structures replaced stone temples.

A page had turned in Angkor.

This was the period when present-day Cambodia

began to emerge, and the country

gradually acquired its current borders.

The Khmer empire, which covered a large part

of the Indochinese peninsula,

saw its vassals free themselves from its grip

and become formidable adversaries.

The powerful kingdom shrank

until it became the smallest country in the region.

Wat Bo Monastery, in the town of Siem Reap.

Part of the memory of the temples

of Angkor is preserved here.

Its reverent has collected hundreds of objects

from the golden age of the Khmer empire.

Dozens of ceramic pots, but most importantly,

a wealth of sculpted bronze artifacts,

most of which are fragments.

There is a huge quantity of bronze here,

More than 1.3 tons, which the reverent

of this monastery decided to retrieve over 10 years ago.

In fact, he kept seeing looted items.

In the 1980's and for a good part of the 1990's,

all the archaeological sites in Cambodia

were looted extensively.

And rather than see these items disappear,

he decided to collect them, to buy them.

This collection represents just a fraction

of the tons of bronze, gold, and silver

mentioned in the inscriptions of Jayavarman VII's time.

Many of these objects

are decorative elements from temples.

The most refined pieces would not look out of place

in the world's great museums.

All of this treasure caught the eye

of anyone who visited the kingdom.

It was the object of everyone's desire, naturally.

And it's clear that this treasure was a source of conflict.

People fought over it at the time.

This type of object is extremely valuable.

That's why there are so few left.

Many of them were stolen.

But we shouldn't generalize.

The decline of Angkor cannot be explained

by a raid to loot these treasures,

even though such raids were frequent

in the history of the Khmer empire,

and continued until fairly recent times.

Angkor's demise was a gradual thing.

The kingdom was not swept away by a single dramatic event.

The city did not lose its power and become dependent

in the space of several decades.

It took well over a century.

Scientists know that a combination of factors

led to its demise.

Climate change, soil erosion,

and the breakdown of the water management system.

This inexorable chain of events

caused Angkor to sink into oblivion.