How Did They Build That?

The inside stories behind a new, horseshoe-shaped complex in Rotterdam, a rock-shaped opera house in China and a makeover of the British Museum.

The engineering secrets behind a mobile research station in Antarctica, a gravity-defying concert hall on the Canary Islands, and a rotating boat lift in Scotland.

The American Museum of Natural History in NYC gets a cave-like extension; an arts center inspired by migrating birds is built on a lake in China; Boston University gains a fossil-free, Jenga-like tower.

A new performance center with a tent-like glass-and-steel lobby tests engineers in Kansas City; two twisting apartment towers make heads spin in Ontario.

Traveling from Canada to Belgium to the Southern U.S. to examine an eye-popping school, museum and railway station and reveal how they were built.

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.

A 1.2 million square foot office building balances precariously on a 39 foot wide base in Chicago. A building named Pterodactyl lands on top of a Los Angeles parking garage. And the world's longest suspension footbridge.

Exploring the design and engineering stories behind D.C.'s Museum of African American History, the Montreal Tower and the Equinor building in Oslo.

Visiting the Hearst Tower in Manhattan and Jewel Changi Airport in Singapore to understand how they were built; covering how designers and engineers attempt to create a museum worthy of Salvador Dali in Florida.

Uncovering the design and engineering secrets behind the Grand Canyon Skywalk, the Audain Museum and more.

Peek inside a cloud-inspired library in Canada that's built over a live railway; see how clever engineering helped a huge Seattle skyscraper go up without harming its iconic neighbour, then cross an Australian bridge that floats above a busy river.

The engineering secrets behind the world's steepest mountain railway, a remodeled 145-year-old museum and a futuristic condo.

A London railway station; giant Singapore biodomes; eye-catching hospital in Las Vegas.

Visiting London's Gherkin, Seattle's Evergreen Point Floating Bridge and Lyon's Musée des Confluences to uncover how and why they were built.

An unstable high rise, an otherworldly museum, and a towering cliffside elevator.

Challenges beset a sculptural new transportation hub for New York's World Trade Center; Amsterdam gains a building inspired by a mountain valley; a new launchpad for space travel prepares for liftoff in the New Mexico desert.

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; in Dallas, a five acre park is created.

Paying tribute to the brave, gravity-defying design of the U.S. National Medal of Honor Museum; traveling to Singapore for a look at a leaning tower of gambling, then exploring a New York City office building that lets the sun shine through.

Visiting Australia's One Central Park, the Oslo Opera House and the California Academy of Sciences in San Francisco to reveal their architectural secrets.

A dazzling new 1400 foot tapering skyscraper is built right next to New York's Grand Central. A curving wine museum requires ingenious engineering in Bordeaux, France. And possibly the world's most glamorous parking garage.

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.

The engineering secrets behind a massive sky garden in Singapore, the world's most slender tower in Brighton, and a railway station in the shadow of Vesuvius.

Celebrating one of humanities biggest engineering achievements, the International Space Station, a meteor proof lab bigger than a football field, constructed by astronauts traveling 250 miles above us at 17,500 miles an hour.

A sculptural high-rise with rippling balconies breaks the mold in Chicago; Mammoth machines bore 26 miles of tunnels for an underground railroad beneath London's city streets.

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.

Building an eco-friendly visitor center 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.