Original subtitles

You got to have restaurants and grocery stores

It's hard to get guys to work in 90-degree weather

And pick block and brick up all day.

It's not an easy job.

Narrator: So, if we built a great wall

Around the united states,

We'd quickly run out of bricklayers.

Even if we could train them,

We'd need to make sure we could accommodate them all.

You know, if you're building a big project

In the middle of nowhere,

You got to have hotels, gas stations.

♪

To feed your guys,

So that would be my first question, would be,

How are we gonna feed the machine of manpower

To produce this wall?

Narrator: To answer this question,

Many masons today turn to sam.

♪

♪

♪

♪

Narrator: Sam would definitely help us cut down our manpower needs.

Relied on soldiers, prisoners,

And these troops were basically people who were

Defending that northern border to keep the huns away,

And they were successful militarily.

And then, the general just kept the soldiers stationed there

And then started to rebuild and to connect those walls

That had already existed.

Narrator: This back-breaking construction

Was also done by prisoners and forced laborers.

We would use paid skilled workers for our project,

Which brings us to our biggest potential expense.

Narrator: Ancient chinese emperors

Narrator: The more sam works, the more we'd save.

And forced laborers to complete their great wall.

Today, we would hire and pay skilled workers

To build our walls.

We don't have a final tally yet,

But this might be the most expensive part of our plan.

It is the manpower.

Not only is it the largest cost,

But it's the most difficult to keep consistent.

Where we have some great guys, it took years to get the crews

That we have now versus how it was 20 years ago.

We're envisioning not one

Operate the heavy machinery,

And oversee these walls from start to finish.

And we have a lot of territory to cover.

How long would it take? [ ticking ]

How much would it cost? [ cash register dings ]

Could we even pull this off?

♪

Narrator: We're imagining what it would take to recreate

One of the wonders of the world, the great wall of china.

In order to come close to the full length

Of the great wall,

Breathing skilled workers to help lay the stone,

But two brick walls

Along the land borders of the united states.

Made out of long-lasting materials

And by skilled workers, our walls might be so great,

Seeing them will be on people's bucket lists.

I don't know whether you know a chinese saying --

"he who does not reach the great wall cannot be a true man."

When we're growing up in china,

That sort of concept actually deeply rooted

In our mentality that great wall

And if we have to transport materials,

♪

But before we can add up our final costs,

We'd still need to get our team in place.

And since our crews would be working in the southern heat

And the northern cold, we'd need to make sure

They'd be prepared for all types of weather.

♪

Narrator: The great wall of china

Took the lives of almost a half-a-million workers.

♪

We would make sure everyone is safe on our jobsite.

About 300,000 troops,

We're going to borrow an idea from our local ski resort.

Narrator: So, plans for our great walls are coming together.

We're taking it one barrier at a time.

We have a location along the northern and southern borders

Of the united states.

We decided on our material -- brick walls,

Prefabricated off-site.

We'll prime the pump and then we hit go.

Narrator: We'd call on a handy robot, sam,

But we would also need a total of 1,000 living,

It binds with the fired clay on the brick,

Turns out, the chinese had a secret ingredient,

One that grew all around them.

In modern times right now,

We're using something called mortar,

Which is mixture of cement, lime, sand, and water.

In the old times, they clearly don't have cement

So they used sticky rice,

And the lime, and probably sand, and the water mixture.

Narrator: Our workers wouldn't need to use

What's in their lunch box to build our walls.

Luckily for us, modern brick has the stickiness built right in.

♪

And basically what happens is when you lay the brick,

You put the mortar on there.

The brick pulls the moisture out of the mortar,

And that creates the bond.

Narrator: And, thanks to modern advancements,

We'd be able to get things done much faster today

Than they did in ancient china.

Liu: You actually could build a section of the walls

Off-site somewhere

And then bring on-site to assemble them together.

Is a lot more environmentally friendly than making steel.

Narrator: The great wall of china is still standing tall

After thousands of years.

We're contemplating what it would take to build two walls

Along the american borders that would last just as long.

Even though, today, we have access to more modern materials

Like steel, we've decided that we would use brick,

Just like the ancient chinese did.

The brick, essentially, that's coming out of earth,

They fire the bricks in ovens,

And then that's pretty much the final product.

So the entire process of making brick

So that's one way of potentially, you know,

[ equipment whirs ]

Narrator: But the brick-making process

Is more complicated than it may seem.

Bricks are made of shale, which is soft layer of rocks,

And then they grind the rocks into almost powder,

And then mix it with water to form a very stiff clay mix,

And then the mix will form something called a slug.

And then there will be a cutting process

To cut the slug into sizes.

Narrator: What goes between the bricks is a different matter.

So, let's figure out how we build it

But not everyone agrees with the idea of a wall.

I don't know that there's a political will

To put up a chain link fence on the border at this point.

There's so much opposition to the very idea of it.

♪

Narrator: Assuming everyone was in favor of our walls,

We'd make them out of brick.

But not just any brick -- prefabricated brick panels.

We'd want our walls to be as distinctive

As the great wall of china,

But stronger and more durable.

And its neighbors to the north and south.

And who would do the work.

The united states has about 300 million residents.

China is approaching 1.5 billion people.

A big population is an advantage if you want to build a big wall.

♪

During the qin dynasty,

The emperor had an army of people to call on.

[ swords clanging ] [ people shouting ]

♪

During his years, the qin emperor sent out

Which is typically about a day.

Speed up the process.

Hibbard: In today's processes, most everyone extrudes brick

With a high-pressure, low-moisture machine,

Presses the brick out into a column,

Goes through a machine that pushes it through the wires,

Cuts it into the individual brick,

Basically sets it on a car,

Takes it into a preconditioned shed for a day or so,

And then it goes through a drying process,

Which is about three or four days,

And then it goes into the tunnel kiln for the firing process,

Is one of the greatest achievements in the world.

So, generally, about a week from the time you extrude the brick,

You can start packaging that brick

And have it ready for shipment.

Narrator: Brick also has another benefit -- its life-span.

Basically, the brick made today will last forever.

♪

Narrator: We're envisioning a wall that would nearly equal

The length of the great wall of china.

We'll actually have to build two to come close.

They'll mark the boundaries between the united states

We'll start building simultaneously

♪

♪

First, we'll drill down and set up a strong foundation.

Terrain is always a factor,

And that's where we're in close communication

With the jobsite contractor and engineering.

It takes a lot of labor, it takes a lot of design,

And it takes a lot of people involved

To make sure it's done right and done safely.

Narrator: Then we'll gondola in the brick walls,

Made tough enough to last for centuries.

Now it's time to get started.

On the east and west coasts.

We'll give a bonus to the construction team

That reaches the middle first.

We'll install statues of the emblematic bald eagle

In the most visible locations.

We did it!

We built barriers above and below

One of the largest countries in the world.

We used brick, one of the most trusted construction materials.

We used the latest digital technology and robotics

1,000 workers plus an army of robots like sam

♪

Narrator: We're conjuring up a modern-day wall

That's greater than the great wall of china.

Here's our plan -- we're going to get the brightest minds

To plan a route that follows the border

Between the u.S. And canada in the north,

And the u.S. And mexico in the south.

We'd want to use stable rock to anchor our wall,

Then bring in prefabricated brick panels.

We would transport them by gondola over the mountains

And by helicopter over remote areas.

To get the job done.

Would put it up at super-high speed.

Then, we could consider giving our walls a distinctive look.

Liu: The bricks or blocks,

Actually you could make different textures

And make different colors,

And then you could have some patterns.

Narrator: We'd cover our great wall with the red, white,

And blue of the american flag

And add iconic stars that will fluoresce at night.

It's going to take us 10 years and 1,000 workers.

Indicates that we're simply not that different

[ planes whooshing ]

We know not everybody will be excited,

But maybe some people will gain a greater sense of security.

We are a species of wall builders,

And even where there are no border walls,

There are always walls.

Tens of thousands of micro-walls,

Walls around the homes of the rich,

Around gated neighborhoods.

I don't think walls are going anywhere anytime soon.

The fact that we continue to build walls

Because this is more than a wall.

From the generations of people that came before us --

That we prefer not to fight.

That we prefer to have other people

Or other things guard us.

Narrator: We're hoping that like the great wall of china,

The strength and design of our walls

Will spark awe and enthusiasm for generations to come,

And that it might be a reminder

Of what great things can be accomplished

If we built it today.

[ fireworks exploding ]

It took us 10 years, required 1,000 workers.

So, how about our budget?

We figured $2 trillion for bricks,

At least $18 billion to transport the wall in panels,

Another billion for labor,

And half-a-billion for the latest in surveillance systems.

No one's going to get over this wall

Without our knowing about it.

It's starting to add up.

We're looking at a grand total of $2.25 trillion.

But we have an idea to help bring down the cost.

[ cash register dings ]

We'll invite all the leaders in the world

To the greatest fireworks display ever.

♪

We'll invite the biggest stars to stand atop our walls

And perform in a concert they'll talk about for generations.

[ cheering ]

We'll christen the walls on the 4th of July

And hold an anniversary event every year

To help pay the maintenance costs.

♪

Down there no bigger than a canal is the border.

Could probably build from two ends

And then meet in the middle.

Narrator: We'd want this wall done quickly,

But the border with mexico is a major speed bump.

♪

It may look idyllic from a saddle,

But for a structural engineer, it's a bit of a nightmare.

Just ask a local like linda walker.

♪

I'm standing in the united states,

And that teeny-weeny little strip of rocky water

Obviously, you need multiple teams coming in --

That is the international boundary between us and mexico.

Everything that you see on that side, from the trees on up,

Is another country.

When they drew this boundary between us

And mexico along texas, they chose to use a river.

They didn't use a straight line.

It's inconceivable to imagine

How long this would take to build.

Narrator: But that's the thing about great walls --

They seem impossible.

There's a lot of planning before the first brick can be laid.

Narrator: The ancient chinese built their wall by hand.

It took 2,000 years.

We'd want to build our wall much faster than that.

And we know sam can dramatically speed up

The process of brick laying.

Narrator: And then there's all the time

We could save by using computer technology.

In theory, we could do it in a decade,

So we're ahead of the game, right?

Well, we may be forgetting one thing.

In today's world,

And, you know, get up high enough

To build a wall of that scale, you need to do a very thorough

Structural analysis, foundation analysis.

And then you need to go through

Environment impact assessment.

Narrator: We're hoping that by using a natural material like brick

And doing the work with the help of robots,

We would ace the environmental assessment.

Then, we'll have to consider the foundation,

Or should we say, the many foundations we'll have to build.

Here's an idea that will cut our build time in half.

Such as india, as a deterrent to terrorism.

Out of the river." no.

First of all, half of that water belongs to mexico,

Not so sure that's gonna work out real well.

Narrator: There seem to be quite a few obstacles

Standing in the way of our plan.

But other countries are still finding ways to build walls.

Countries are building walls around the world today.

Some of them don't technically fit the definition of a wall.

They are, you know, high-tech fences,

But they serve the function of a wall.

Those walls are being built in many countries,

So you'd go, "okay. Well, we can use water

Same can be said for israel and saudi arabia.

In other countries, they're being constructed

To deter unwanted migration.

You see that especially in southeastern europe.

Narrator: We know two border walls could be controversial,

But if this country decides this the antidote

To our anxious times,

We think we can build two walls in 10 years.

We're almost ready to build this thing.

So, how staggering will the cost be?

And get us a straight shaft

And it doesn't look as though

The chinese wall follows a straight line either.

If the chinese could build their great wall by hand,

Surely we could manage with today's technology.

But we have our work cut out for us.

Our geological challenges range from building into solid rock

On a steep cliff or slope down to a river basin

Where we just have uncontrolled alluvial deposits

That are soft, compressible.

But for the most part, we can get modern equipment

In the way of augers to drill down

The wall is still standing today.

Where we'll sock it into that rock.

♪

Narrator: So, let's sock it to the most stable rock,

And dig six feet underground to prevent any tunneling.

The foundation work would definitely take a while.

But we'll plan to fly our wall in in pieces to save time.

♪

This region is vast, and it's dry.

To avoid any delays, we would need water to keep our equipment

And our workers cool.

Narrator: But that wouldn't work for us during warmer months.

Along the northern and southern borders of america.

♪

When considering this massive undertaking,

We can learn from the original.

When the great wall was constructed,

The chinese took advantage of the colder seasons.

Sun: In winter, they would fell some of the trees to have a slope

And then to pour water down and let the water freeze

So then they have this smooth slide

That could make transportation a lot easier to carry large rocks.

♪

We have to imagine building two walls

Venegas: The heat can cause the hoses to overheat

And the hydraulic fluid to rupture the hoses.

The machinery is actually very hot to touch.

You have to be very careful when you're climbing onto it

That you don't burn your hands as you're climbing up and down,

Even to get a break.

♪

Narrator: And if would require a massive workforce.

We know, back in the qin dynasty,

There were about a million laborers

Is one of the greatest achievements in the world.

And it was bridges that were built in order

To make invasions possible.

Could we do it? Oh, yeah, we could do it.

Yeah, it would be expensive, but we could pull it off.

♪

Narrator: After two millennia, the great wall of china

Has become more than a dividing line,

It has become a symbol of national pride.

When we're growing up in china, that sort of concept, perception

Actually deeply rooted in our mentality,

That the great wall

Being involved in the construction.

Narrator: We want to know how the ancient chinese

Managed to pull off such a remarkable feat.

So, for the challenges of transporting building materials,

Like moving bricks, to the top of a hill,

You know, people had carried these bricks on their backs.

When the slope was not too steep,

They can use donkey-pulled carts.

♪

Narrator: To come close to the full length

Of the great wall,

We have become a more secure world

By the time of the ming,

There was mainly the concerns about the mongols.

And by the time of the end of the ming,

The concerns were about the manchus.

Narrator: Attila the hun may not be lurking

Over the next hill in america,

But every age has its own worries.

And walls make some people feel safe.

Walls do provide a certain degree of security,

But the more we become accustomed to security,

The lower the threshold required to trigger our insecurities.

And so it was a military defense.

In the past several decades,

Especially since the end of the cold war.

We just don't feel it,

And therefore we are wracked by what would have been considered,

I think, lesser concerns 20 years ago,

30 years ago, 40 years ago, but those same concerns are,

You know, driving us to distraction.

Narrator: We've been building protective walls

Since the 21st century b.C.

In many ways, the history of the walls

♪

For us to commit that amount of people,

That amount of labor someplace in the world

Would likely only be to save our planet.

If we were to start over today trying to recreate

That physical barrier

Which is a very large, massive wall,

And we look at the prototypes

That have been proposed for this,

Even given our technology today, the best estimates tell us

That we would have had to started this

Sometime right after the war of independence.

It was walls that were built in order to deter war,

Narrator: But why would we consider building one today?

City walls, historically,

Were especially effective at repelling attacks.

If you don't believe me, just ask attila the hun

What he thought of city walls.

♪

Narrator: More than 2,000 years ago,

China was facing threats inside and outside its country.

They build this wall to protect themselves,

Basically to keep the tribal peoples from raiding, looting,

-- Captions by vitac -- www.Vitac.Com

Narrator: But perhaps the greatest thing about the great wall

Was its spectacular failure.

Once you have this wall built, it may not be efficient enough

To keep the archers or the arrows away.

♪

Narrator: We're on the jobsite of one of the world's greatest wonders.

And we're wondering -- how long would it take?

How much would it cost?

How many workers would we need?

Could we even do it if we built it today?

♪

Was something that will never happen again in human history.

Captions paid for by discovery communications

♪

Narrator: It's the most famous wall on the planet,

And the longest structure ever built --

The great wall of china.

It's probably one of the most recognizable landmarks

In the world.

Narrator: It begins in the gobi desert

And snakes its way east

All the way to the border of north korea.

You're only as good as your foundation.

Narrator: They say good fences make good neighbors.

Frye: We've been building walls for at least 10,000 years,

Beginning with the city of jericho, the biblical city.

Narrator: We're exploring the engineering epic of the longest wall

In history, the great wall of china.

One of the seven wonders and also the longest manmade

Structural defense system from ancient times.

Narrator: But do we have the need for a new great wall today?

Modern designers are on the fence

About what makes a great wall.

Man: Whatever you're setting on,

♪

And if you don't do it right,

That scaffolding's gonna come down.

Narrator: The great wall of china is one of the greatest

Architectural achievements in human history.

It's the number-one wall.

Narrator: But hundreds of thousands of people perished putting it up.

Their remains have never been found,

And some say it's because they lie within the wall itself.

Castle: The amount of skilled labor in the thousands

That they were able to apply and put on their project

The wall of china must have been built over centuries,

♪

Narrator: 10 million people travel

To the great wall each year

To take a once-in-a-lifetime walk.

The biggest and the best and the most beautiful,

Most architecturally pleasing, structurally sound,

Actually used as a defensive barrier

Is the great wall of china.

Narrator: It took 2,000 years to build.

Could we use modern technology to build a wall

Like this in less time?

The great wall is about seven times longer.

And, you know, we can't even wait for a highway

To be built in two to four years.

It's ridiculous to try to build a wall across.

It's just simply an enormous undertaking.

It's almost impossible.

Narrator: And does the world even need another great wall?

Historically, walls were constructed for the purpose

Of diminishing conflict, deterring attack, or invasion.

You know, it's ironic a lot people nowadays say,

"build bridges, not walls," but historically speaking,

Narrator: It's as high as a 4-story building...

The wall is actually more than one wall,

It's a series of walls built starting in 717 b.C.

♪

Liu: The emperor of qin dynasty, ying zheng,

Decided to connect all those walls

Together to form the initial form of the great wall later.

The most recent section actually was built in the ming dynasty,

That's about 1300 a.D.,

And that's the section actually most tourists

Around the world visit every year.

♪

Is the history of civilization.

♪

...And is wide enough to accommodate

A horse-drawn carriage.

But it's most well-known for its length,

More than 13,000 miles long.

♪

That's the equivalent of more than halfway around the world,

A lot longer than any walls being considered today.

♪

Liu: The american and mexico border is about 1,900 miles.

With blades, with large industrial equipment.

And to cut and address stone to different shapes.

Narrator: Some of the greatest buildings in the world are made of stone.

So, could we use it for our wall?

♪

[ whirring ]

Venegas: In this particular area, we're gifted with masons

That still can do rock masonry walls.

It's a dying art.

We don't have that type of labor skilled with their hands

To be able to accomplish that anymore.

We don't cut stone by hand, we cut stone with machines,

During that period, they learned probably how to chisel

♪

Narrator: So, our walls would be forced

To have a more modern look.

What about concrete?

So, to me, you know, aesthetically,

It's just a chunk of concrete,

It doesn't have that unique character that bricks

Or even rammed earth offer.

And secondly, when you have a massive concrete structure,

Think about the hoover dam.

But they do have a lot of soils and the rocks,

The next big question is, what could we build it out of?

The oldest portions of the ancient chinese wall,

Which most tourists never get to see,

Were made of what's called rammed earth,

The same color as the nearby desert.

They perma-mix the soil and the rocks

And the small stones together,

And basically just hammer down to compact to form a shape.

Mind you, that was built around 700 b.C.

So they don't really have a modern technology

To make bricks,

You will be dealing with the thermal cracking.

And they somehow figure out a way to make a stable structure

Just by compacting them into shapes.

♪

Narrator: It would be almost 10 centuries

Before the chinese would invent the wheelbarrow,

Easing the burden of generations of wall builders

And earning the eternal gratitude

Of gardeners everywhere.

While in the mountainous area of the country,

The ancient chinese built with stone.

And then transport

It's not integrated well with the environment.

Steel more feels like a foreign material

When you see it within nature, with trees, with soils.

And the third, I think there might be a long-term

Corrosion problem, as well.

So that will also raise the maintenance cost.

Narrator: We wouldn't want our walls to crack, rust, or even worse.

Why don't we look into one of the strongest-

And longest-lasting building materials in existence -- brick.

Liu: You can mass manufacture bricks and the blocks.

And the stones, you have to quarry the stones

And secondly,

Because they're heavier and will have heavier

Transportation cost than the other two materials.

Narrator: Brick is a combination of good looks

And low maintenance.

It would be the perfect building material

For our two hypothetical walls.

Brick was eventually used to finish construction

Of the great wall of china, but the ancient chinese builders

Also added an unconventional ingredient

That just might be the reason

Castle: It has properties that make it susceptible to weathering,

♪

Narrator: Here's the cold, hard truth about concrete.

If it's mass concrete -- that is,

Bigger than 3 square feet -- there's a lot of surface area

That reacts to a change in temperature.

The problem is the inside takes longer to adjust.

If, for instance,

The interior has been slowly heating up and expanding

While the outside is quickly starting to cool and contract,

Something's got to give.

It's called thermal cracking.

Oceans to the east and west act as natural barriers in our plan.

Wearing, it's gonna break down eventually.

The rebar inside of it can corrode, expand.

And for these reasons, I really don't see concrete

As a viable solution for a wall

That needs to last several thousand years.

♪

Narrator: We wouldn't want the repair costs for our walls

To be as insurmountable

As the walls themselves, so let's consider steel.

So, one, it's expensive to have a steel wall of that size.

Narrator: A lot people were happy to see the berlin wall

Rather than a beginning.

They hoped that it would avert thermonuclear war

And de-escalate tensions.

The kind of strength we build in the united states

Will be the defense of freedom.

Frye: John kennedy said,

"a wall is a hell of a lot better than a war."

What changed opinions was the presence

Of western news correspondents in berlin

And ever after the wall has been symbol of infamy.

♪

They saw it as the end of a crisis,

Come down in 1989.

And walls have been a contentious subject ever since.

Frye: There's no doubt that the berlin wall

Was the key to our re-evaluation of walls.

Walls for most of 10,000 years were entirely noncontroversial.

♪

Narrator: It seems there are pros and cons

To constructing a modern-day great wall,

But before we draw up our blueprint,

We need to decide if it's worth taking on the challenge.

Frye: At the time, the roman empire was the defender

Every man was trained to be a warrior,

He was trained to defend his community.

The building of walls alleviated that necessity,

And that enabled men to follow different avocations,

To specialize in different things,

To become writers, artists, scientists, philosophers.

♪

Narrator: In the u.K.,

You can still see the remains of hadrian's wall.

It was built in the year 122 by emperor hadrian,

Primarily to keep the scots out of the roman empire.

Narrator: The great wall of china helped protect and unify

Of much of civilization on three continents.

So what the romans were concerned about were

The people they knew as the barbarians.

Narrator: The most infamous wall in modern times is the berlin wall.

The nearly 12-foot-high cement barrier

Was built to keep east germans from defecting to west berlin

When the city was divided after world war ii.

Frye: Construction of the wall was scary to people on both sides.

Outside berlin, western leaders oddly enough

Viewed it with a sigh of relief.

A hostile environment can improve a wall,

Especially along the southern border with mexico.

Walker: If you were to fly over this,

The sheer amount of uninhabited landscape

Is mind-boggling.

You have a million-acre national park,

You have a 350,000-acre state park,

And you have ranches that are typically in the 200,000

To 300,000-acre size range.

It's big, and it's rough.

♪

Narrator: But we have an engineer who says

But we'd need to consider the tricky terrain,

Especially if it's as hilly as china.

So, these large grade changes made it incredibly difficult

To access the wall, so even if an enemy

Was to scale a mountain or a hill or a ridge

To get up to the base of the wall,

They then had to try to get up and over the wall.

Narrator: So, we'll be prepared to handle

Any bumps in the road.

America's top and bottom land borders

Equal over 6,000 miles.

That's the directive that will guide every decision

One of the most populated countries in the world.

We're imagining what it would take to do that around america.

We have the great wall in china already,

Serving as a symbol of culture,

Civilization, human wisdom, achievements.

Walls provide a physical barrier,

And as long as they're guarded, they tend to be very effective.

A wall was a tool, it's a force multiplier.

Narrator: So, what would it take to erect a structure

That's impressive, innovative,

And built to last for the next 2,000 years?

♪

We consider about our two new walls.

What route are we going to take?

What kind of materials will we use?

How are we going to do it?

Who's going to build it?

How long will it take?

And how much will this whole thing cost?

We're envisioning two walls across america's north

And south borders, but we need to map a precise route.

Our walls wouldn't have to be quite as long as china's,