Dupont Underground is an art exhibit situated beneath Dupont Circle in Washington. Abandoned for years, the underground space has been given new life by artists in the city who want D.C. to be known around the world as an arts center. (Victoria Walker/The Washington Post)

Just as party elites are debating whether the unwashed masses can be trusted to pick America’s presidential nominees, a small experiment in democracy is taking place beneath Dupont Circle. In an abandoned streetcar station, New York-based designers Josh de Sousa and Nancy Hou have given people the freedom to make whatever they please, with an art installation called “Raise/Raze.”

The exhibit, which opened Saturday, is housed in a tunnel that closed in 1962, reopened briefly as a food court in the 1990s and has been abandoned since. In 2014, the group Dupont Underground got a five-year lease from the city to use the tunnel as an art space. It chose “Raise/Raze” from among several proposals because of its interactivity, according to board member Philippa Hughes.

“This exhibit is all about people working together to build things,” she said at a preview Friday.

The artists behind “Raise/Raze” agree with her assessment.

“Since this is D.C., we definitely saw [the exhibit] as a sort of democratic form of sculptural communication,” de Sousa said at the preview. “I just hope they don’t tear down all the ‘trees.’ ”

By Sunday, the “trees,” graceful spires at the far end of the tunnel, still stood, but they were noticeably thinner. Visitors had apparently pilfered some of their parts — bricks made of the same 3-inch plastic balls that served as the “ocean” at the National Building Museum installation known as “The Beach” — and built a little village nearby.

“So far, we’ve seen people build a lot of houses and chairs,” de Sousa said.

James Reid, David Whyman, Aidan and Ava work together to build a fort. (Sadie Dingfelder/For Express)

Bucking the trend, David Whyman, 17, worked on a freestanding arch. Then he spied a family of three laying down a foundation for a fort.

“Hey, let’s work together,” Whyman called out. “I can make the doorway for your house.”

If humanity’s tendency to cooperate was evident during the first weekend of “Raise/Raze,” it was even more conspicuous beforehand. In the runup to the opening, 1,400 volunteers toiled for 3,000 hours to make building blocks from the “Beach” balls.

The most stalwart volunteers worked until 3 a.m. before opening night, but they fell short of their goal, using fewer than half of the donated balls. That’s perhaps why, as the walls of Whyman’s fort reached knee height, the builders began to run short of supplies.

“Go find more three-by-fours,” said fellow fort builder James Reid, dispatching his 11-year-old twins to scour the hall for unused bricks.

As the Whyman-Reid fort began to tower over neighboring structures, Whyman reflected on his team’s success.

“It’s interesting how much more you can achieve when you work with other people,” he said. “I’m studying right now for my AP World History exam, and this really parallels early history, where you have bigger groups of people coming together from hunter-gatherers to build early cities.”

An hour later, Whyman and the twins posed in front of their fort. It was an impressive structure, nearly 6 feet tall, with spires, windows and a long hallway.

Alas, even great civilizations eventually fall. For the Whyman-Reid city-state, the end came in the form of a little girl in red. She toddled, unseen, around the back of the fortress and began pulling bricks from the wall. Reid watched the destruction with equanimity.

“It’s like making sandcastles at the beach,” Reid said. “You just have to take a picture and walk away.”

Dupont Underground, New Hampshire Avenue just northeast of Dupont Circle; Wed. & Thu., 5-7 p.m., Sat. & Sun., 11 a.m.-5 p.m., through June 1, $16.82. (“Raise/Raze” is sold out, but walk-ins will be admitted as space allows.)

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