New Yorkers can take the subway to Coney Island and Angelenos can cool off in Venice or Santa Monica, but Washingtonians are out of luck if they want to hit the beach—the shore is a three-hour drive away.

Alex Mustonen and Daniel Arsham, partners of the New York design studio Snarkitecture, thought that Washington, D.C. could use a beach of its own. So they created one inside the National Building Museum, filling a giant pit with almost a million plastic balls that visitors can float on or swim through. The pit, which opened on the Fourth of July, is fronted by a beach of artificial turf, complete with deck chairs and umbrellas. The BEACH, as the installation is aptly named, is entirely white, a Snarkitecture trademark.

The BEACH is the follow-up to the museum’s wildly popular installation last summer, the BIG Maze, designed by Bjarke Ingels Group. Ingels recommended Snarkitecture for the job this time around. The studio is known for work that straddles the worlds of art, architecture, and fashion, such as a ghostly pop-up shop for the fragrance line of retailer Odin and runway sets for the fashion label En Noir (these, appropriately, all in black).

Like Ingels’ maze before it, the BEACH revels in the immense scale of the museum’s 300-foot-long Great Hall. Including a concession by Union Kitchen, a local food-business incubator, it sprawls over 10,000 square feet of the museum's rich 19th-century interior. A mirror along the back wall seemingly doubles the length of the AstroTurf pier.

It’s been reported that Arsham is color-blind (hence the studio’s strict adherence to black and white), but Mustonen makes it clear that his condition is only partial and the limited palette is a purposeful choice: “A lot of it’s about reduction and simplicity—taking away all the texture and color, and things that exist in our day-to-day environment,” he says.

Lying on your back in the plastic sea, the ceiling seems as distant as the sky. Visiting definitely feels like an escape from the everyday, and there’s no risk of getting sand in your eyes.

The BEACH is on view at the National Building Museum from July 4-September 7, 2015. Tickets are required.