Over the weekend, there was a rare moment of celebration at the US-Mexico border: children from both countries played together on pink seesaws straddling the steel border fence separating El Paso and Juárez, Mexico. The almost surreally joyous scene was a temporary art piece titled Teeter-Totter Wall, meant to foster a sense of unity between the two nations.

The art project, which has been a media sensation, is the work of architecture studio Rael San Fratello, a partnership between San Jose State interior design faculty member Virginia San Fratello and UC Berkeley architecture professor Ronald Rael, author of the 2017 book Borderwall as Architecture: A Manifesto for the U.S.-Mexico Boundary.

Ten years in the making—the duo drew up conceptual sketches for the project in 2009—the piece was inspired by the Secure Fence Act of 2006. It features three pink seesaws, which are installed between the slats on the border fence, which allow people on either side of the border to see one another.

“The border is a literal fulcrum for US-Mexico Relations, and building walls severs those relationships,” wrote San Fratello in an email to artnet News. “The wall, and the unfortunate politics of the wall, not only separate countries, but regions, cities, neighborhoods, families, and more recently, a separation of children from their parents.”

In contrast to heart-wrenching scenes at the border that have filled the news in recent years, the unveiling of Teeter-Totter Wall was a joy-filled occasion. Overseen by Mexican soldiers and US Border Patrol agents, families on both sides gathered to play during the temporary installation, which lasted about a half an hour.

“Everything was designed in advance to be assembled quickly. The fulcrum that supported the seesaw was notched to sit on the border wall temporarily,” said San Fratello. “We were delighted with the turnout and excited to see the children having so much fun on the teeter totters!”

“Art is such a powerful vehicle for change,” wrote Refugee and Immigrant Center for Education and Legal Services (RAICES) on Twitter, calling the project “a beautiful installation at our southern border.”

A prototype for the sculpture was included in “The U.S.-Mexico Border: Place, Imagination, and Possibility,” at Craft Contemporary, Los Angeles, one of the Pacific Standard Time: LA/LA exhibitions in 2017. A 2014 etching for piece appeared in “Insecurities: Tracing Displacement and Shelter” at New York’s Museum of Modern Art in 2016, along with five other pieces by the duo, all of which are now in the permanent collection of MoMA and SFMoMA.

The architects have also devised other border wall interventions such as the interactive, instrumental Xylophone Wall; Burrito Wall, which would install an open-air kitchen against the fence with a counter for diners to eat on both sides of the wall; and Wildlife Wall, with special openings to allow animals to move freely, as well as observation walkways for people on both sides.

President Donald Trump made plans to build a border wall between the US and Mexico a centerpiece of his 2016 campaign, but has yet to do so. The confrontation over the issue ensured a partial government shutdown for 35 days at the start of the year when Democrats refused to provide funding for the project. In response, Trump declared the issue a national emergency in February. After months of legal challenges, the Supreme Court ruled in his favor last week, approving the use of $2.5 billion in Pentagon funds to fund work on a US-Mexico border wall.

Other artworks responding to the proposed border wall have included a wall of cheese and a golden fence surrounding Trump’s Mar-a-Lago hotel in Palm Beach, Florida.