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How do you thread a brand-new subway
through a crowded city-centre?
Building a tunnel there
is one of the most challenging things you could ask
a tunnel engineer to look at.
How did two revolutionary towers
save an inner city from the sprawl of the burbs?
It was out of this world to do it back then.
It was absolutely revolutionary.
And how do you join two nations
when a bridge can't go the distance?
Where can we dig?
Where can we build up?
It was a puzzle.
Welcome to a world where anything is possible.
The space where innovation and creativity collide.
Part building, part transformer.
It's incredible.
Where the only limit is human imagination.
Dr. Mabry: This is mind-blowing when you think about it.
We're talking about actually living on another planet.
Unpacking the miracles
and mysteries of construction...
This was engineering
on a scale the world had never seen.
...to ask,
How Did They Build That?
I talk a lot about skyscrapers that are built to break records.
But not all of them are built to show off.
Some are built to show up.
The Marina City Towers in Chicago did just that.
And somewhere in the process,
Chicago's most serious urban solution
took a form no one expected,
one that looks a lot like corncobs?
It was a revolutionary design...
Nothing like this had been built before.
...constructed against the clock...
Marina City found so many ground-breaking ways
to be efficient.
...using cutting edge methods of building.
Pretty much every aspect of the construction
was revolutionary.
And it would create two towers
that still define the skyline almost 70 years later.
So, how did they build them?
It's late 1950s America,
and the boom in car ownership
is busy transforming the country,
as a vast network of highways draws people in businesses
out of the cities and into the suburbs.
Few are feeling the shift more than Chicago.
There was a question as to how cities
were going to survive.
One of the people searching for a solution
is William McFetridge,
President of Chicago's Building Services Employees Union.
It was a large union.
It had a healthy pension fund
that needed to be invested,
but it was also threatened by this kind of migration
of people and companies out of the city
into the suburbs.
Together with local architect Bertrand Goldberg,
they hatch a plan.
McFetridge and my father were kindred spirits
about trying to reinforce the city.
Dr. Agbedor: Goldberg was inspired
by modernist architects like Le Corbusier,
who believed the modern city
needed to be completely rethought.
And he imagined creating communities
where every aspect of everyday life
could happen all in one organized setting.
The big idea was a city within a city.
And this would create, in his view,
a much more vital, much more vibrant,
much more energetic, er, urban space.
What Goldberg proposed
was unlike anything Chicago had seen before.
The city's first twin tower multi-use complex,
housing everything from shops and offices,
to homes and parking.
A sort of vertical city within the city.
Goldberg's design for two 65-storey
residential towers with an office, theatre,
and retail space
will truly fulfill his ambition of a city within a city,
but comes with a lot of challenges.
At 587 feet tall,
the first will be keeping them standing
in the soft clay soil.
Next, they'll need to build fast
to keep costs down,
but constructing the towers in record time
will require some radical solutions.
Then, to lure people out of the suburbs,
they'll need to come up with an ingenious way
to fit in a parking space for all 896 apartments.
Lastly, with an eye on cost again,
they'll need to find a system to build the apartment floors
in superfast time.
These will be truly revolutionary towers.
Back then, living in a 60-storey high-rise
was absolutely unheard of.
Chicago was home to the first skyscraper
built in 1885.
Even so, this will be a first for the city
and for Goldberg.
His tallest building was a three-storey house
out of concrete,
er, so he had no experience
in actually building anything of this size.
I mean, these were the tallest towers
at the time in the world.
Despite this,
Goldberg's vision convinces McFetridge
to invest millions of the union's money
into making the dream a reality.
McFetridge was taking a gamble
from an investment point of view.
Who knows whether a development is gonna work or not.
November 22nd, 1960, they break ground
on this revolutionary build.
This is not typical ground-breaking.
You have the mayor.
You have The Archbishop of Chicago.
You have a phone call live with John Kennedy
as president-elect.
I mean, this is pretty significant stuff.
Their first problem
is ensuring the concrete towers won't sink.
Concrete, by its nature, is very heavy,
and so, therefore, these immense towers,
erm, like, you know, 65 storeys to the very top,
um, are enormously heavy.
The job is complicated
by Chicago's notoriously poor clay soil.
The enormous loads could not be supported
by the weak, very compressible soils.
Holding the towers up demands some of the strongest
foundations ever seen.
Using the world's biggest drill,
weighing some 125 tons,
the guys on site cut deep shafts over 100 feet
down into the bedrock beneath Chicago.
And then, steel casings were lowered into the holes
before being filled
with concrete and steel reinforcement,
so that's to ensure
that they would remain rock solid.
Then, 154 foundation piles
are arranged in concentric circles
to support the circular towers.
You can rest the building, er, on top
of those very, very long concrete pillars, basically.
With the foundations complete,
it's time to start building the vertical city.
Everything about this project is revolutionary,
right down to the way in which it's built.
It was one of the first uses in North America
of what was called a Linden Crane,
which was a swinging crane that could actually
basically lift itself up, the building structure.
Doing that will cut down on the time spent
moving the crane.
That means a shorter schedule
which reduces cost.
Normally, you would have to
basically build the scaffolding,
and then, lift the crane up.
And it was a very cumbersome procedure and took time.
Innovation doesn't stop there, though.
They also try a new system of concrete casting
called jump form.
Today, it's used a lot in construction,
but back then, it was revolutionizing
how tall buildings were made.
Carpenters built a wooden mould
around the tower's concrete core
that can be removed and used over and over again.
They'd pour one floor's depth of concrete
and let it set, and then, the next day,
they simply move the whole thing up a floor.
No one had ever done this before.
Each day, the core increased in height
one entire storey,
so an amazing pace of work.
With the concrete cores complete in record time,
the team faces a new challenge.
1960s America sees car ownership exploding,
and one of the pulls of suburban living
was to be able to park your car right outside your front door.
The challenge for Goldberg
was to create inner city living
that could compete.
In 1960s Chicago,
the team building two revolutionary city towers
is trying to figure out
how to fit in enough parking garage
for the 896 apartments.
In a normal parking garage,
each floor needs its own ramps and turning areas
to connect one level to the next,
but Goldberg didn't have space for that.
So instead, he designed a single spiral ramp
that climbed the building with parking on its outer edge.
There's no wasted space in the ramps.
Everything is either a drive lane or a car.
Covering 19 storeys on each tower,
the architects create parking for every apartment.
It's unheard of at the time.
Having this much parking
in buildings like this
was a bold statement by the architect.
By the fall of 1961, the team moves on
to building the 40 floors of apartments above.
Unlike the circular floor plate of the parking level,
the residences have these beautiful
shell-shaped balconies.
They needed to be beautiful,
but also to be built quickly
and that called for simplicity.
So each floor follows the exact same design.
This meant that the same concrete moulds
could be used again and again and again.
They could simply, once the concrete
had cured on one level,
lift them out, move them up,
and use them again.
What this meant was that the site
could almost be a constant assembly line.
Using timber moulds is all well and good
for flat floors.
But creating ones that curve for the balconies
will be far more complex...
...until James McHugh, boss of the concrete company,
sees a solution.
James McHugh was an avid sailor
and, er, had his, er, fibreglass boat
on Lake Michigan.
And he had the eureka idea,
like, fibreglass is the perfect way
to form these, you know,
really amazingly complicated shapes.
Creating the moulds from fibreglass
makes casting the curving concrete balconies
much simpler.
It's a technique that's often used today,
er, but McHugh really pioneered it,
er, on Marina City.
The repeating floor plan
also brings another major advantage.
The construction process
was choreographed almost like a ballet.
It meant trying to make each task repetitive
so that the crews would be practised,
er, and be able to lay the reinforcement
or to pour the concrete
or to move the forms as quickly as possible.
By tightly scheduling every trade
on a repeating 48-hour cycle,
the team is able to complete each floor in just two days.
Doing a two-day floor cycle
is ambitious even today.
It was out of this world to do it back then,
it was-- it was absolutely revolutionary.
With this incredible speed,
the first tower tops out just one year
after construction began.
The fact that there were two towers
meant that a crew could work on one tower one day,
and as that concrete came up to strength,
the next day, they could work on the other tower,
so there was no idle time.
In January 1963,
the Marina City Towers complex is ready for its residents.
With 896 apartments
across two towers and an office, theatre,
and shops below,
it transforms downtown living,
creating Goldberg's vision of a city within a city.
Marina City showed that you did not
have to go by normal conventions.
You could rethink the puzzle.
Architecturally bold,
built using innovative construction methods,
the 65-storey Marina City Towers redefine
what high-rise living can be.
The buildings were so stunning
and they looked so new and so modern
that people rented them out very, very quickly.
Those 19 spiralling floors of garage
gets to park their car.
While below, there's even space to moor your boat.
Seventy years after completion,
its new residents love it every bit as much.
I love how you have the full-height window
so you get all the light, you get all the view.
To me, it just feels like the perfect place to live in.
I really, really love the idea
that there's--just the access
to all the amenities of the city
and a lot of them contained within the building itself.
All thanks to the vision of union boss McFetridge
and Architect Goldberg.
These buildings are celebrated,
and their design, it resonated with people then
and it resonates with people now.
The fact that it has become
a cultural landmark for the city
for over 60 years puts a smile on my face.
Denmark really, really wanted a tunnel
linking them to Sweden.
Sweden really, really wanted a bridge
linking them to Denmark.
And instead of arguing forever,
they met in the middle, literally.
The Oresund Link starts as a bridge,
disappears into an island, and finishes as a tunnel.
That's what I call compromise with style.
It would take over a hundred years to realize...
The technology at the time was just not up to it.
...involve engineering ingenuity, never seen before.
It's one of a kind.
It's, er, a lot of solutions
tried for the first time.
It couldn't be one long tunnel...
It wasn't a tunnel all the way,
because it was much more expensive
than a bridge.
...but it was impossible to be all bridge, too.
It's basically at the end of a runway.
This is the Oresund Link.
So, how did they build it?
In Northern Europe,
the Scandinavian countries
of Denmark and Sweden
sit separated by the Oresund Strait.
Building a crossing between the two countries
has long been a dream.
The first plans to join Denmark and Sweden
were proposed back in 1865,
but the immense costs just killed that idea.
Then, in the 1930s,
the arrival of the car
saw the re-emergence of that idea,
but the Second World War put an end to all of that.
Sixty years later, in 1991,
Denmark and Sweden commit to bridging the gap.
The idea behind it was, of course, growth,
trying to bring Denmark and Sweden together.
But there is a problem.
In fact, two.
A bridge wouldn't work on the Danish side
because it was too close to Copenhagen Airport
and dangerous for planes,
but creating a ten-mile-long tunnel was too expensive.
The solution is to have a bit of both.
Oh, and they also need somewhere
for the bridge and tunnel to meet.
It became three pieces, four kilometres tunnel,
four kilometres island,
and eight kilometres of a bridge.
The vision is to create a stunning bridge from Sweden,
a tunnel from Denmark,
and then, join them together on an island.
The only thing is,
none of this, including the island,
currently exists.
So, they will need to create 320 acres of artificial island
in the middle of the strait.
But they're not allowed to change the water flow
as it could damage the delicate ecology.
It's too expensive to bore a tunnel
for just two and a half miles,
but it can't sit on the seabed
because it would affect the water flow too,
and be a hazard for ships.
The bridge will also need to be strong enough
to carry cars and heavy trains.
But it can't have a lot of columns
because ships will need to pass underneath.
Creating it will take an incredible amount
of engineering ingenuity
We haven't had infrastructure project
like this, er, before.
They can't even think about lifting a spade though
until they've worked out how to build it
without damaging the ecology of the strait.
You have salt water and fresh water species
living side by side in a very delicate balance.
Any change to water flow could be catastrophic
for marine life.
Where can we dig? Where can we build up?
Where can they put bridge pillars?
It was a puzzle.
In August 1995,
work starts on the first piece of that puzzle,
building the artificial island
so it's strong enough to stand up to Mother Nature.
There can be stones.
First, you needed to put large, what we call armour stones.
The large stones act as a breakwater
in order that the waves cannot erode the island.
Now, they need the material
to build the island up behind the rock wall.
The solution? Dredge it from the seabed.
Dr. Cosgrave: This was ingenious,
because the lowering of the seabed
increased the water flow, compensating for the island.
And they could use what they dredged up
to create the artificial island.
Each day, they remove 31,000 cubic yards
of limestone, sand, and soil from the bottom of the sea,
the equivalent to over nine Olympic-sized swimming pools.
It was dredging, and then, transported,
go out, more dredging, transported back.
So that was a massive logistic operation.
But then, they hit upon a big problem.
During, the dredging process,
we found un-exploded bombs from the Second World War.
In Sweden and Denmark,
the team behind a dual bridge and tunnel project
that will join the countries together
has dredged up a big problem on the seabed.
In fact, 16 of them
in the shape of un-exploded World War II bombs.
If just one detonates,
it will jeopardize the whole project
and could risk sinking passing ships.
We had to call the military
and they, er, came out.
One by one...
...all the bombs are detonated.
With the bombs dealt with,
they get on with moving almost 318 million
cubic feet of material to complete the island.
And in the summer of 1996, the team finishes.
Their next challenge is building the tunnel
that connects the island to Denmark.
Normally, you bore under the seabed,
just as they did to build the Channel Tunnel,
which links Britain and France.
But here, the seabed consists of fractured rock
and shallow soft sediment,
which means tunnelling would be way too expensive.
The cheaper option is to lay the tunnel
on the seabed,
but that isn't gonna work either.
You don't want something going up from the seabed
in order to create the risk of ship collision.
So they decide to dredge a channel
and lay the tunnel inside of that.
Then, each 580-foot long tunnel section
is prefabricated on the shore.
Each one, an enormous rectangular tube,
measures 30 feet tall and 130 feet wide.
At the time, there was no immersed element
of this size that had ever been produced.
Each section is then filled with air
and floated out to sea before being sunk
exactly where it's needed,
which with each weighing 55,000 tons
seems a tall order.
It's called the Archimedes principle
and it means that if an object is lighter
than the amount of water that is displaced,
then it floats.
Like when you try to push
a ball underwater,
it's pushed back up to the surface.
Now, they need to get the massive tunnel sections out
into the middle of the sea.
It was daunting,
finding how to get it across.
They had three or four towing boats
in order to manoeuvre.
Using GPS, each piece is floated
to its exact position above the trench,
ready to be sunk.
They filled water into the ballast tanks.
So the tunnel were heavier,
and then, with wires from the towing boats
gently down into the trench.
For a whole year, work goes smoothly,
submerging a section every month.
Then, they reach number 13.
It was being lowered into place.
We lost water tightness
because one of our bulkheads
was pushed in by water pressure.
In seconds, the volume of the element
was filled with water.
And it just sank
at an uncontrolled position.
There's now a 55,000-ton concrete tube
sitting in the wrong place.
I remember arriving on site,
there was really a sense of emergency.
You could feel it in the corridors.
They're forced to refloat the whole section
and inspect it for damage.
It ended up being only fairly bad,
er, because we could re-employ the structure.
In September 1998,
unlucky number 13 sinks perfectly to the seabed.
Six months later, they connect with the island.
The tunnel was the longest
immersed tube tunnel in the world.
Now the team starts work
on the five-mile double-decker bridge
that will join Sweden to the island.
Its central span needs to cross a busy shipping lane
with as few supports as possible.
The first job is creating solid foundations
up to 65 feet beneath the surface.
They were positioned within a tolerance
of 20 millimetres on top of the bases.
With equal precision,
they then start building two super tough towers.
Each will be 670 feet tall and has to be strong enough
to carry the weight of the bridge.
It will withstand a Boeing 747
if it flies into the pylons.
Meanwhile, 1,200 miles away in Spain,
the double decker sections are fabricated one at a time
before being shipped to Sweden.
The site space in Malmo was restricted.
You might be able to store one or two,
but then they had to go out
and be placed in the bridge line
before the next ones arrived.
Time is of the essence.
Each enormous section has to be lifted into place
by a 300-foot tall floating crane
called the Swan.
And then, this is repeated again and again
with no room for error.
Both concrete decks weigh 7,000 tons.
And when you add the lifting gear,
which was 1,800 tons,
you're very close to the capacity of the Swan.
It was at the limit.
The slightest miscalculation
risks a bridge deck at the bottom of the sea.
The whole program had to be stitched
very tightly together.
Amazingly, the final piece slots into place
three months ahead of schedule.
It was probably the only project
that I have heard of this scale
which was finished ahead of time
and on budget.
After five years of construction,
and at a cost of $4 billion,
July 1st, 2000, the Oresund Link opens,
creating a permanent connection between Denmark and Sweden.
It was a wonderful day
when, er, we could actually move across
from Denmark to Sweden.
Beautiful day, beautiful day.
It's a very elegant design, I must say.
For the whole Oresund Region,
it is, er, both a landmark and icon,
but it's also very important to get the area to grow.
A tunnel sunk beneath the sea,
a bridge strong enough to carry rail and road traffic,
wide enough for ships to pass below,
and an island created from nothing.
You'll fly in and you see the bridge and the island,
and then, it just disappear into the ocean.
It's an amazing view.
With more than eight million people
crossing it every year.
It has been a massive success,
because we are much tighter between Sweden and Denmark.
An engineering marvel
that has transformed the region's fortunes.
This was something special.
It was a fantastic experience.
Sydney's population kept climbing,
and the city needed a new metro station.
Only issue, no space.
So engineers did the one thing that made sense,
they went underground.
"Properly Down Under,"
as the Aussies would say.
And what they built deep beneath the city
is a station that proves sometimes
the only way forward is down.
At the turn of the 21st century,
Sydney, Australia
is one of the world's fastest growing cities.
Sydney's population was around three and a half million people.
It's now projected in ten years' time
to reach six and a half million people.
But when it gets to moving around,
close to four million residents rely on the rail network
built in 1855
to carry passengers between the suburbs
or they get in their cars.
High-quality, fast public transport
is absolutely fundamental
to improve the quality of urban life
for the citizens of a city.
It needed a big solution.
A plan for a state-of-the-art
driverless metro system
gets the go-ahead in 2011.
In total, it's an investment
of about $60 billion
to create a brand-new high-capacity
automated metro network for Sydney.
In 2014, work begins
in the city's Northern Suburbs,
digging 22 miles of metro tunnels
heading towards the central business district.
But there's one question that needs answering.
We needed a station
right in the middle of the CBD, close to town hall,
close to the offices, close to the shopping,
but the big question was where do you put it?
Because the CBD is already busy
and we landed on this location on Pitt Street.
There were eight buildings,
which included a 14-storey tower,
which sat at the location
where the station needed to be built
some 66 feet below.
The site also holds deep historical significance
for the First Nations people, who must be recognized.
The Gadigal people are the first peoples
of this country and particularly this city.
They have been here for over 65,000 years.
All of which makes for a very difficult build.
Foster and Partners,
the architects behind London's iconic Gherkin
and the Millau Viaduct in France,
rise to that challenge.
You're seeking to integrate
the very nature of that excavation
to guide you through the world above
into the world below.
Foster's vision for the flagship subway station
and 500-foot tower above is stunning,
but constructing it comes with a series of headaches.
Starting with tunnelling twin station platforms
that have to somehow squeeze between the street
and a major tunnel underneath.
Next, the team must work out
how to support the huge office tower overhead,
but they can't run the building's core
through the station
to anchor it into the bedrock below.
Then, they need to find a way
to flood the station's vast entrance hall
with natural light,
despite being in one of the city's
most built-up districts
and sitting at the base of a 39-storey tower.
Finally, they must honour
the traditional custodians of the land.
A lot to do then.
August 2017, work begins.
We had to demolish a number of existing buildings,
office buildings, shops, et cetera,
to make way for the station below ground.
And below ground is just as busy
and crowded as above.
Building a tunnel there
is one of the most challenging things
you could ask a tunnel engineer to look at.
In Sydney, Australia,
the team building a new metro system
is facing a major challenge.
There's abandoned railway "ghost" tunnels,
sewage mains, electricity tunnels,
building basements.
It's like Swiss cheese down there.
Including one of Sydney's main road tunnels
running 70 feet below ground,
right through the site.
That tunnel was just 12 feet or so
below the floor of Pitt Street Station.
It leaves precious little space
to squeeze the station platforms
between the tunnel and the city streets above.
Usually, subway stations are created
by boring one big tunnel
that's big enough to have two platforms,
side by side, one in each direction.
However, here,
there wasn't enough space to do that.
The ingenious solution is to dig two small tunnels
which come together at the station.
It's a technique called bifurcated binocular design.
There's two tunnels which run underneath
two different streets,
which are a block apart.
So hence, you get these two parallel tubes
which look like a pair of binoculars,
hence the name.
What makes for a very complex build
is in that part of the busy CBD.
The biggest challenge is excavating
where the metro needs to pass
over the Cross City Road Tunnel.
You see these tunnel boring machines,
they are huge machines,
they're hundreds of metres long, massive,
bigger than big jet aeroplanes.
They're mobile factories.
Scott C: It was a pretty hair-raising period of time.
It's 12 feet above a live operating road tunnel,
which in engineering terms is wafer-thin cover.
The rock mass could not support the weight
of the 700-ton machine.
The danger is, it collapses
into the road tunnel below.
Their best bet? To try an engineering technique
more commonly used in bridge building.
The bridging slab was a little bit wider
than the Cross City Tunnel,
so approximately 15, 16 metres wide,
and it was approximately about a metre deep,
but it followed the profile of the Cross City Tunnel
to basically spread that load around the tunnel crown.
The 45-foot-wide,
three-foot-thick bridging slab is in place.
But the team prepares in case it isn't strong enough
to support the weight of Nancy,
the massive boring machine.
Out of abundance of caution,
er, we closed the Cross City Tunnel.
We had a minute-by-minute plan
of where our tunnel boring machine should be
throughout a night shift,
so that as the tunnel boring machine
was pushed across,
its loads would be transferred
either side of the Cross City Tunnel.
After a tense few hours...
The bridging structure worked perfectly.
We had movements, deflections of less than five millimetres.
So it was a resounding success.
And on August 15th, 2019,
Nancy safely breaks through
into the station entrance hall.
The team turns to its next challenge.
Building the 39-storey office block on top.
When you build directly over a station,
there are some great advantages,
but some great challenges as well.
You would ideally bring the core of the building
right down to ground level.
But our ground level
is occupied by a station,
so there's no space.
The team's solution is unexpected and brilliant.
The tower above the station
is effectively on a concrete table
with columns that run through
the entranceway into the station,
and then, transfer out onto the bedrock below.
To do that, the columns need
to support forces of 90 million pounds.
That's equivalent to 11 space shuttles
firing at full throttle.
These columns were four feet by eight feet
by approximately 75 feet long.
They contained
about 400,000 pounds of concrete
and 70,000 pounds of reinforcing steel.
With the columns set,
the tower's core quickly rises above the station.
And within months, all 39 storeys of the office
are taking shape.
The team's next challenge
is how to get enough natural light
into the station hall,
despite being overshadowed by the tower above.
Daylight is hugely important in environments
like subway stations.
In emergency situations,
underground experiments have shown
that people instinctively follow pathways
that are naturally lit,
even when evacuation signs
point them in another direction.
So we cut this big slot in the face of the tower
to pull it apart,
to get as much daylight into the heart
of the entrance concourse as possible.
Scott K: It was an extremely challenging structure to build.
Heavy structural steel,
twenty-five mil thick glass,
um, above the station entries.
For the commuter exiting the station,
it's also a pathway to the light.
All that's left to do
is install the escalators and elevators
that will carry thousands of passengers every day,
and fit out the station's concourses,
before the final job,
recognizing the First Nations people
whose ancestors lived on the land.
The Gadigal people are a clan of the Eora Nation,
which are the original Aboriginal people of Sydney.
For thousands of years,
they relied on a fresh water source
that they called the Tank Stream,
which today runs deep below the city of Sydney.
The Tank Stream is reflected in huge murals
and the city decides to name the station
after the Gadigal people.
My involvement was actually putting forward
the names that we recommended,
and Gadigal was that name.
I'm extremely proud
that we finally have some true recognition.
In August 2024, after seven years
and a cost of 324 million US dollars,
the newly named Gadigal Station
completes a stunning addition
to Sydney's Metro system.
Serving 16,000 passengers a day.
Being part of something that leaves that lasting legacy
where you are benefiting the community as a whole
is something I'm very proud of.
It's been a highlight of my career,
just because it's very democratic.
People use it day in, day out.
And it's there for everyone.
Spanning an entire city block
with a huge 39-storey tower on top,
its inviting entrance hall,
is open plan and airy,
thanks to four mega columns,
and a pair of stunning 10,000-tile murals.
The scale is such that you could see it
from the street as well.
And as you move towards it,
you know, it begins to just grow and grow and grow,
and then, people come and they're sort of enveloped
by colour.
And a year after opening, Gadigal is recognized
as one of the most beautiful stations
in the world.
It's an absolutely stunning piece of engineering
and a stunning piece of architecture.
It really is a beautiful, incredible station.
It's more than just catching a train.
In a world where imagination,
innovation, and creativity
define the spaces that surround us,
How Did They Build That? shows again and again
that humankind will overcome the seemingly impossible.
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