Original subtitles

Narrator: venice,

One of the most iconic Cities in the world.

Home to spectacular Medieval structures,

All linked by winding canals.

Venice is a city Built on water.

It's magic and unique.

Narrator: constructed on Unstable islands in the middle

Of a lagoon,

This impossible city Defies all odds.

Can its ancient origins Reveal why it is

Created here and how it is Still standing?

Today, scientists use Pioneering acoustic

Imaging technology to scan Venice's canals.

Narrator: and dive into The lagoon's deep trenches

To hunt for clues to The city's ancient roots.

Is a shocking death pit evidence Of venice's dark history?

We found thousands Of skeletons.

Narrator: and can a Revolutionary new megastructure

Stop venice from sinking Beneath the waves?

To solve these mysteries,

We unearth venice's Ancient foundations.

We deconstruct the famous Rialto bridge,

Uncover sunken ships,

And come face-to-face with The city's buried victims

To reveal the secrets of this Magnificent floating city.

Venice,

An iconic city

Sheltered in a lagoon in The northeast of italy.

This spectacular medieval Attraction welcomes over

20 million visitors

Every year to its megastructures And grand canals.

[ boat horn blowing ]

With every inch of The islands covered

By building, everyone and Everything travels by water.

Canals are Its main streets,

And people use them To get around every day.

Narrator: but this extraordinary City has humble beginnings.

1,600 years ago, venice is Just a marshy lagoon.

Today, it's a city Like no other,

A patchwork of Over 100 islands

Connected by 400 bridges

And 30 miles of canals.

At its heart is St. Mark's square,

Home to the iconic Clock tower and basilica.

It's a city brimming With history,

Created from centuries of Immense wealth,

Conflict, and power.

How does this extraordinary Lagoon city

Come to be, Rising from marshland

To become this Magnificent masterpiece?

Guido giordano ventures to An uninhabited island

Three miles From the city center

To look for Clues to the city's origin.

He wants to investigate what Venice looks like

Before people live here.

A lagoon is the environment

That forms when major rivers

Meet the sea.

Narrator: the lagoon is formed Thousands of years ago,

When the po and the piave Rivers reach the adriatic sea

And drop tons of sediment Into the water.

Over thousands of years,

The sediments pile up to form Hundreds of marshy islands.

Giordano: This material is very soft.

There's also this plant That decompose,

And they make up that Particular type of material

That we call peat.

Probably the softest Sediment on earth.

Narrator: How did the venetians build

A city on these seemingly Impossible islands?

Knowing their territory And the resources available,

They cut wooden piles from The local forest

And used them to reshape The islands.

Narrator: The ground beneath venice

Is riddled with wooden piles.

Millions of them are driven Into the water-logged silt.

Packed tightly Just six inches apart,

They form a solid foundation In the soft soil.

On top, wooden planks And slabs of limestone

Create a strong base

For the venetians to build

Monumental masterpieces like St. Mark's basilica.

Are these foundations Enough to

Keep venice's majestic Buildings standing strong?

The millions of Wooden posts have

Stood resilient beneath Venice for centuries.

They are a triumph of Ancient engineering,

And they transform the muddy Islands into solid ground,

Stable enough for thousands of Homes, churches, and palaces.

But the 30 miles of snaking Canals create fractures

Across the islands that put The buildings at risk.

Venice's canals are Naturally formed by

Water that flows Between the islands.

The largest, the grand canal,

Runs for 2.5 miles and has 170 houses along its banks.

The buildings that Teeter on the edge

Of the water are at risk of Sudden collapse

If the ground gives way.

Fantina madricardo Patrols the canals

To hunt for any signs Of danger.

Narrator: She uses innovative technology

To scan the sides and bottom Of the canals

Throughout the year and detect Any minute changes.

Narrator: fantina sends Soundwaves down into the water.

When the soundwaves Bounce back,

She records them to create A 3d image of the canal floor.

Narrator: when fantina studies The canals over time,

She discovers Something surprising.

They're constantly shifting.

Narrator: The constantly moving

Current erodes The banks in some places

And deposits new Sediment in others,

Changing the depth of The canals and the shape of

The islands.

But this is not good For a permanent city,

So medieval venetians come up With a clever solution.

First, engineers barricade The canal and drain the water.

Then they drive Wooden piles into

The soft ground along The edges.

On top, they build thick Brick walls and face

The inner edge with Impermeable stone

To make the walls waterproof.

When they refill the canal,

The solid walls prevent The water from eroding

The islands so the venetians Can build on every bit of land.

The walls still stand To this day.

Along the canal banks, The venetians

Construct stunning buildings, Like the doge's palace

And salute church.

They create one of the most Magnificent cities in the world

On land that should be Impossible to build on,

And to help reduce the load On the canal walls

And foundations, the venetians Have another clever trick.

Instead of heavy stone,

They use light brick to Construct their buildings

And build arches into The walls to lighten the load

Even more,

Creating the iconic facades of Venice we see today.

But modern life In this bustling city

Creates a new problem.

Narrator: the boat traffic Causes erosion

And degrades the walls Of the canals.

Fantina's monitoring Is crucial to

Pinpoint areas of walls That need repair,

So they will last for Centuries to come.

The medieval venetians Maximize every bit of land.

They turn the city into one Of the richest in the world.

How does venice Become so successful?

Can secrets buried beneath

Its most famous landmark Reveal clues?

Narrator: venice,

A megastructure suspended Above the water.

This engineering marvel Becomes one of

The richest cities In the medieval world.

Why is it so wealthy?

One of the city's Greatest landmarks,

The rialto bridge, May hold clues.

It's an engineering wonder,

Standing on 12,000 wooden poles

That stop 10,000 tons of

Bridge from sinking Into the muddy ground.

Massive masonry blocks form Strong foundations

At either end.

A single arch of Limestone blocks

Spans 94 feet Across the grand canal,

The widest canal in venice.

And two rows of covered arches

Turn the bridge Into a marketplace,

An engineering masterpiece, One of

The first of its kind In the world.

Why is this bridge so Important to venice's success?

In the seventh century a.D.,

The venetian islands are All separate towns.

Each town has a central Square, water well, and church.

But as venice grows, The venetians

Build bridges to connect Neighboring islands.

Iconic structures like The bridge of sighs

And the bridge Of the three arches

Allow residents to move easily Across the city,

But the enormous grand canal Divides the east and west.

It spans more than 200 feet In some parts

And seems impossible to Bridge -- for centuries,

The venetians try but are met With disaster.

In 1181, They launch long pontoons

To create A floating bridge.

It connects the east and west For the first time.

Heavy foot traffic Wears it down,

So the venetians build A wooden tower bridge

In its place, Allowing ships to pass.

In 1310, it burns down In a revolt.

The venetians rebuild it,

But it collapses again And again from constant use.

Leading architects compete To build a new stone bridge,

But even michelangelo fails To beat the winning design.

The rialto bridge connects The east and west.

Now every venetian can travel Across the city

To buy and sell At its beating heart,

The rialto market.

International traders Sail up the grand canal

To dock by The famous bridge.

What are the venetians Selling that

Draws merchants From far and wide?

Giovanni caniato Heads to the west side of

The bridge To the bustling market

That continues to this day.

He believes the answer is

A surprisingly simple product -- Salt.

In order to preserve fish, Preserve meat,

Preserve everything, You needed salt,

And salt was needed also For agriculture,

For lots of other reasons.

So salt was what's today The petrol.

Narrator: salt is Commonplace now,

But in the middle ages, It's one of the most precious

Commodities in the world.

Its global importance is Equivalent to that of oil today.

Salt was

One of the reasons why venice Was so powerful and so rich.

Narrator: the shallow waters of Venice's salty lagoon are

Ideal for the production of This valuable mineral.

The venetians cleverly used Their land to produce it.

They find themselves At the heart of

A global salt trade.

People come from all over The world to buy it.

The riches transform venice

Into a magnificent Renaissance city.

Visionary architects design The doge's palace,

The immense bell tower, And the spectacular basilica,

Buildings unlike anything The world has seen before.

But venice isn't only A beautiful destination --

It becomes A global powerhouse.

Can an astonishing Underwater discovery

Reveal how venice Expands its reach

And becomes the most powerful Navy in europe?

Narrator: Venice.

In the middle ages, It's a global powerhouse.

How does this city Become so influential?

A clue may lie in

An astonishing discovery Found in the lagoon.

Eros turchetto

Knows these waters better Than anyone else.

Every week, he heads out To search for clues

Of venice's past.

Narrator: on one survey, eros Makes an incredible discovery.

Three miles Southwest of venice,

Preserved in the muddy bed Of the lagoon,

Eros uncovers the hull of A rascona,

A flat-bottomed medieval Transport ship.

And next to it, the skeleton Of an even bigger boat,

125 feet long,

Dating from The early 14th century.

On its bow,

A carving reveals A clue to what

The vessel looks like In its prime.

What is this mysterious ship,

And what can it reveal About the rise of venice?

♪♪

Narrator: the team of marine Archaeologists erects

Enormous steel walls

Around the site And analyzes the discovery.

The lack of oxygen Under the mud

Helps preserve the remains Of the ship.

The team records every detail.

Narrator: this is The only boat of its kind

Discovered in europe.

Narrator: this is no ordinary Fisherman's boat,

But a warship From the 14th century.

What does this Incredible vessel

Reveal about the rise Of venice?

Stefano medas is an expert In venice's medieval history.

He heads to a gigantic complex In the city to find answers.

Narrator: In the city center,

Just half a mile From st. Mark's square,

These massive buildings cover Over 5,000 square feet,

1/6 of venice's Entire land area.

It's here that the venetians Build ships

Like the one unearthed In the lagoon.

Narrator: an arsenal is where The military makes weapons

And equipment.

Normally, a warship would take Many months to build,

But this enormous Factory allows

The venetians to Revolutionize shipbuilding.

In a dry dock,

Master shipbuilders First build the frame

And then clad it With wooden boards.

Next, they fit the ship With masts

And tow the hull To the next station

To hoist the sails.

And, as if On a conveyor belt,

The ships pass from dock to dock To be loaded with guns,

Ropes, anchors, and oars.

This efficient system enables The venetian military to

Build a whole ship In a single day,

Making venice a formidable Naval power.

The venetians pioneer one of

The world's first Production lines.

Narrator: thanks to this Arsenal, the venetians are able

To build the most powerful Navy in europe.

They ruled territories As far as modern croatia,

Greece, and cyprus.

But their success comes At a cost.

A discovery on A secluded island in

The venetian lagoon reveals A deadly catastrophe.

How can venice survive Its greatest setback?

Narrator: Venice -- 600 years ago,

It's one of the richest cities In the world.

It attracts merchants From all over the globe.

But could a macabre discovery On a nearby island reveal

That, in the middle ages,

Venice is on the brink Of collapse?

The tiny venetian island of

Lazzaretto vecchio hides A chilling secret.

Buried beneath the courtyard

Is a mass grave,

Hundreds of bodies Cast into a pit,

One on top of the other.

Forensic analysis shows The bones belonged to men,

Women, and children,

A mix of europeans, Africans, and asians.

Why are more than 1,500 people from

Across the world buried On this tiny island?

And what is the cause of Their death?

Lara meneghini leads A death pit investigation.

Close examination of The bones reveals no sign

Of cut marks or blunt trauma To the skulls.

There's no evidence of murder.

Lara believes it must be An invisible killer.

We found thousands Of skeletons.

We think they died For the plague.

Narrator: The hundreds of people are all

Victims of bubonic plague,

A contagious bacterial disease That begins

In central asia In the 14th century

And repeatedly hits europe.

Death pits like these Have been

Discovered on multiple islands Within the lagoon.

Why are these people All buried together

On these islands?

Lara searches for clues in A warehouse on lazzaretto nuovo.

In the corner of the building, She discovers

Medieval graffiti.

Here we have The drawing of a ship,

Some trademarks, and also A part of a writing telling us

That the ship came From constantinople.

Narrator: Merchant ships carrying goods

To venice are diverted here.

Can the graffiti reveal Why the ships stop

And leave their crew On this tiny island?

So this graffiti tell us The story of a ship, which

Arrived in venice from greece.

The ship had to stop, and people Were here for quarantine.

Narrator: the 16th-century Graffiti is the first use

Of the term "Quarantine" Discovered

Anywhere in the world.

It's proof that as

The venetians are designing Their iconic buildings,

They also invent this disease Control tactic.

In italian, quarantina Means 40 days,

So incoming ships must dock Here at these isolated islands

And wait for 40 days

Before continuing into venice.

Meneghini: This island is the place

Where the quarantine system Was invented.

From here, It was adopted then all over

The mediterranean and then All over the world.

Narrator: the venetians apply This meticulous

Quarantine system To every incoming boat.

Ships destined for venice First unload their crew

And cargo

On an island at the edge of The lagoon.

The goods are laid out In long warehouses

And smoked with herbs In the belief

This will eradicate traces Of the plague.

Any sailors showing symptoms Are sent to

The plague hospital On a neighboring island.

After 40 days of quarantine, Plague-free sailors

And their cargo are allowed To continue on to the city.

A tall brick wall surrounds The island to make sure

That no sailors escape Their 40-day quarantine.

But lara's excavations Reveal that the venetians try

To maximize the chance of Survival for the sailors.

There were about 100 houses.

High walls were used to divide The island in different

Isolation areas in

Order to keep separate people That arrived at different times

Or from different places.

Narrator: the island is Cleverly designed to

Reduce the chance of infection Between ships' crews.

The houses contain Everything needed

For a comfortable 40-day stay.

Meneghini: the houses were Small and basic,

But could house between 2 to 4 people.

These are the ground floors Of two houses divided by

This wall,

And this area is the area of The fireplace.

Narrator: despite their clever Tactical planning,

The city does not escape The killer plague.

In the 1630s,

As many as a third of venice's 140,000 citizens die.

Today, bubonic plague is Treated by antibiotics,

But quarantine is still A vital weapon in the battle

Against untreatable Infectious diseases.

Meneghini: the isolation system, The quarantine system is

Still the public health Response

In use today.

Narrator: this resilient city is Determined to thrive

On isolated islands.

Thanks to its unique Construction in the lagoon,

Venice overcomes The deadly plague,

Builds thousands of warships, And gains immense wealth.

The venetians establish A floating metropolis with

Buildings suspended above The water by wooden foundations.

But why are people So determined

To live in such An unusual setting?

Can new discoveries On the edge of

The lagoon reveal what draws The first settlers here?

Narrator: venice, An extraordinary floating city.

The buildings in This engineering marvel are

Suspended above the water By wooden foundations.

Who are the first settlers Of venice?

And why are They so determined to

Live here on these seemingly Inhospitable islands?

Carlo beltrame is On a mission to

Find out who builds This incredible place.

His team explores The waters to

The north of the city For clues.

Narrator: they hunt for signs Of ancient building works,

Lost over time.

Okay.

Narrator: The divers use innovative,

High-resolution underwater Cameras to map

The bottom of the lagoon.

Hidden on the sea floor, they Discover something remarkable,

A long, narrow stone plinth That looks man-made.

The team analyzes samples of The masonry for clues

To what this mysterious Structure is and who builds it.

Carlo believes details Locked inside

The masonry hold the answer.

Narrator: carlo uses evidence From the survey

To date the roman Pier's construction.

Narrator: this discovery Is significant.

The dating suggests The area around venice

Is inhabited by the romans 2,000 years ago.

Fellow archaeologist paolo Mozzi believes the newly

Discovered pier could

Mean that more roman cities Lie hidden in this area.

♪♪

This evidence indicate That this was not

An isolated settlement,

But it was part of a network Of settlements that was

Covering the northern lagoon.

Narrator: paolo takes To the air to hunt

For more clues to Venice's origins.

He uses aerial photos captured With state-of-the-art

Multispectral cameras To scour the coastline.

The cameras detect the water Content in the soil,

Highlighting Any solid structures

Hidden beneath the surface.

In the northern Part of the lagoon,

Paolo finds evidence of lost Roman infrastructure.

Mozzi: this means that as A sort of a negative of

The image, we could see The plan of the city.

Narrator: complete with temples And theaters,

This lost roman city covers An area the size of pompeii.

There was a settlement

Consisting of houses, Of water wells, and a pier.

This means that people Were really living here.

Narrator: paolo believes This site provides

Clues to why venice Is founded.

He launches A full excavation.

As his team unearths the city Piece by piece,

Its identity comes to light.

This is the lost city Of altinum.

We're now in the heart of The ancient city of altinum.

Their exquisite decoration Shows that

There were very rich houses.

Narrator: altinum is one of The wealthiest cities in

The roman empire in The first century a.D.

Paolo's team excavates The structures to

Decipher the entire plan Of the city.

Mozzi: this street was Connecting the city center

Where the public monuments were

To the harbor on The shores of the lagoon.

In the aerial image, you can See the trace of this street

That was going towards The lagoon and the harbor

From the city center.

Narrator: one structure Catches paolo's attention.

It's much wider Than an ancient road,

And the aerial Images suggest

It's a deep trench.

It leads straight Into the lagoon.

Paolo thinks there's only One explanation.

Mozzi: we could also identify A major canal.

Narrator: Just like venice today,

Altinum is built Around canals.

Is this proximity And similarity a coincidence?

Or can altinum's ruins Reveal the origins of venice?

Paolo scours the ruined houses And buildings for clues.

He analyzes the condition Of these structures

And reaches An extraordinary conclusion.

Only the floors remain, Because after the abandonment,

The walls were destroyed.

Narrator: This destruction reveals

The shocking end of altinum

And the birth of venice.

In the second century a.D., Just seven miles from where

Venice is today,

The port of altinum Flourishes under roman rule.

But in the fifth century a.D.,

The barbarian huns attack The roman city,

And the people of altinum Flee for their lives.

They settle in the marshy Islands of the lagoon,

Building their houses On stilts

And relying on the water For survival.

Over hundreds of years, The islanders flourish.

They build a city naturally Protected from

Invasion by the waters of The lagoon.

The fall of altinum marks The birth of venice.

The refugees salvage the stone And bricks from their destroyed

City and use them to build Their new island homes.

Venice rises against all odds.

It begins as a simple refuge From barbarian attack,

And today, it is one of The most iconic cities

On the planet.

This floating metropolis Thrives for 1,600 years.

But can new research Reveal a threat

To the survival of venice In the future?

Narrator: venice -- a medieval And renaissance masterpiece.

It rises from Humble beginnings

As a refuge for romans Fleeing the invading huns.

But now another threat is

On the horizon For future generations.

Many fear that by the end of This century,

Venice will be Permanently flooded.

The rising water will slowly Erode the foundations of

Venice's iconic structures and Put them at risk of collapse.

The city will sink into The water and eventually vanish,

Disappearing back into The lagoon.

Is this really the fate Of venice?

Four miles across The lagoon from venice,

A small island may hold clues.

In 1328, The island of boccalama

Is home to a monastery

Whose monks realize Their home

Is disappearing Into the lagoon.

The city of venice sends The monks two ships,

Each laden with tons of earth And sand.

The monks sink the ships on The side of the island to act

As a breakwater, hoping to Slow erosion from the sea.

But it doesn't stop The island from sinking,

And by the 1500s, The monastery is

Completely underwater.

Will venice Suffer the same fate?

Guido giordano Heads to one of

The most iconic piazzas In the city to investigate.

Narrator: here in the piazza, Guido finds alarming

Signs that venice Is in real danger.

Narrator: venice is slowly Subsiding into the mud.

Experts believe The city's streets

Will be submerged By the end of the century.

But as well as the long-term Dangers of sinking,

The city faces a much more Imminent threat.

Georg umgeisser works at The marine research center

Of venice.

He studies the city's Water levels.

Every year,

Venice is hit by high tides Known as the acqua alta.

We always had storm surges, We've always had high water.

Normally, high water is During wintertime, november,

February and so on.

Narrator: georg and his Colleagues have launched

A state-of-the-art research And monitoring system.

We have an oceanographic Platform out in the sea.

It's about 15 kilometers away From the coast.

We have wave measurements. We have tide measurements.

And we are then able to Create forecasts.

Narrator: Knowing when a flood may hit

Helps the venetians To prepare for it.

The forecasts give Locals time to raise flood

Barriers in the doorways of Their shops and homes.

Today, georg carefully Monitors the water level

As a freak storm Hits venice.

The floodwaters start To rise dangerously.

This graph shows us the water Level of the last week,

And you can see normal water Levels up to 2, 3 days ago.

And then we have a storm, And you can see,

Yesterday evening, We had high water

Above 1 meter At st. Mark's square.

Narrator: as the storm rages Into the evening,

Georg heads out to assess The flooding.

This is st. Mark's square,

And this is the place where You will see high water at its

Very best, because it's The lowest point of venice.

Narrator: the waters here Can reach more than

4 feet above sea level,

Covering most of Venice's streets.

Here, we have A little bit of water.

It's rising now, But this could be

A situation of every day In the next 50 years.

Narrator: georg's data reveals That the rising waters

Are a devastating threat To the city.

Over the last 50 years, Venice has seen

Regular flooding.

However, in the last two years, It has

Seen an increase In exceptionally

High-level flooding.

In 2019, water levels Hit a record high

Of 6 feet Above the normal sea level.

Something is changing.

Climate change is happening.

Narrator: climate change Is a direct threat

To the city of venice.

It causes rising sea levels And increased flooding.

In an attempt To save the city,

Engineers are nearing Completion of 78 retractable

Flood barriers in the lagoon.

When the sea level Rises during a storm,

The barriers will rise with it To block the water.

Now the barriers have Successfully risen in unison,

A monumental milestone For the project.

The magnificent city of venice Is safe for now.

Venice stands strong For hundreds of

Years in the face Of adversity.

Now this resilient city Is ready to thrive

For hundreds more.

Venice --

From humble beginnings As an island refuge,

It evolves into A global powerhouse,

Building thousands of warships And inventing

Quarantine islands To safeguard its people.

The city flourishes For 1,600 years,

And rises to become The spectacular city

We see today.

And with ingenuity And determination,

The people of venice Will ensure that

It survives for hundreds Of years to come.

♪♪

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