How Did They Build That?

Celebrate one of humanities greatest engineering achievements – the international space station – a meteor proof lab bigger than a football field, constructed by astronauts travelling 250 miles above us at 17500 miles an hour.

A museum, floating on five delicate columns, honors combat heroes in Arlington, Texas. Six leaning towers support a dramatic sky-park casino in Singapore. And a NYC office is carved out to protect an iconic park and greenery below.

A cloud-inspired library spans live railway tracks in Canada. A Seattle skyscraper supports an iconic landmark using speed-core for rapid construction. And the world's first tensegrity bridge floats over a river, on a web of cables in Australia.

Apartments hanging 164 feet above the water defy gravity in Amsterdam. Three rippling towers with the 83rd story left open to prevent it swaying transform Chicago's skyline. And Paris's Pompidou Centre reinvents museums.

A 9,000 ton timber roof is built without stopping flights at Portland International Airport. A museum is buried to keep it cool in Dubai's desert heat. And San Francisco's most hated building gets built against the odds.

A 284ft wooden skyscraper built from 1,200 bespoke pieces tests fire safety limits in Milwaukee. A decaying Amsterdam crane track transforms into elegant glass offices. And a needle-thin tower stacks 28 apartments onto a 21ft-wide plot in Melbourne.

Building an eco-friendly visitor centre in the permafrost on Colorado's Pikes Peak tests the team. A museum is constructed in a disused dry dock that's in danger of collapse. And in Singapore a skyscraper is cut in half to create a garden.

A new museum building bends 1,100-glass tubes to form a facade and tunnels below the water table. A vast 11-storey glass atrium HQ is built on the former Berlin Wall site to represent unity. And NJ's Bayonne Bridge gets a facelift.

A 70,000-seat stadium defies seismic forces and international flight paths in LA. Zaha Hadid's dramatically twisted 33-story tower rises around ancient vaults in Malta. And Germany's elegant 807ft TK Elevator Test Tower corkscrews 54 storeys skywards.

On inadequate foundations, San Francisco's MOMA triples in size creating an exterior light enough to prevent collapse. A 1970s Sydney skyscraper is recycled into a 21st century tower. And in Dallas, a 5 acre park is created above 8 lanes of freeway.