Sky Pool

Look, up in the sky! It’s a bird! It’s a plane! No, it’s just taking someone taking a dip in London’s latest architectural marvel: a crystal-clear swimming pool floating 35 meters (115 feet) in the air. Suspended between two residential buildings—and offering views of the London Eye and Westminster—Sky Pool is the brainchild of developer EcoWorld Ballymore, and the pièce de résistance of its Embassy Gardens mixed-used project. While the fully transparent “swimmable bridge” is meant to evoke a feeling of lightness and effortlessness, the sky-high oasis is the product of hard work. This project has been a six-year effort linking project partners across continents, including HAL Architects and Arup Architecture, structural engineer Eckersley O’Callaghan and U.S. manufacturer Reynolds Polymer Technology. 

Among the myriad challenges: Ensuring the 25-meter-long (82-foot-long) structure—dangling from 10 stories up—could withstand not only the weight of water, but also strong winds and shifting building movements.

“It was an idea that really stood out and that we thought was quite special,” said Ballymore CEO Sean Mulryan. “It’s only because of advances in technology that we’re able to do this.”

The team chose colorless acrylic for the pool’s main structure, which, unlike steel or glass, requires less supporting hardware—and offers greater transparency and less distortion. To build the basin, the team drew on lessons learned from manufacturing major aquariums; constructing the side walls as deep beams that span the 14 meters (46 feet) between the two buildings. A stainless-steel frame—kept out of sight—means the pool’s suspended section remains transparent, with steps and filtration systems installed on the ends. 

After extensive testing of the pool’s strength and stability, the team then had to relocate Sky Pool from the manufacturing site in Grand Junction, Colorado, USA, to its new U.K. digs. First, the 55,338-kilogram (122,000-pound) structure went on a road trip, traveling more than 1,000 miles (1,609 kilometers) to Texas. From there, the pool made a three-week journey by sea to Belgium before arriving home in London. It was a whirlwind adventure requiring police escorts, road closures, and even the removal of traffic lights and street signs.

Once the structure was on-site, it was lifted into its steel frame. Sounds straightforward enough, but execution required extreme precision: The margin for error was only 30 centimeters (1 foot).

Since its debut in late May, Sky Pool has been causing quite the splash on the London scene—and not all of it good. Videos of people swimming in the pool quickly went viral, prompting sheer terror in some viewers. And the architecture critic from Financial Times dubbed it “a disaster that’s already happened.”

For many though, Sky Pool makes for an interesting addition to London’s iconic skyline—an amazing feat, even to the people on the project team.

“There were many times when I thought it wouldn’t happen,” admitted Hal Currey, founder of HAL Architects. “I’m fairly amazed it’s there. I feel a mix of relief and a sense of achievement.”

Sky Pool may be setting off a wave of showstopping aquatic architectural projects, including the latest on the scene: Deep Dive Dubai, billed as the deepest pool in the world.

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