Every two years, staff members at New York City’s Metropolitan Museum of Art get the chance to display their own creations on the institution’s hallowed walls. Since the tradition started in 1935, the exhibition has been something of a secret, open only to employees and their guests, Hyperallergenic’s Elaine Velie reports. But now, for the first time, the show is open to the public.

“Art Work: Artists Working at the Met” features hundreds of pieces—including paintings, drawings, photographs, sculptures and digital installations—made by guards, librarians, conservators, educators, registrars and others who work at the Manhattan museum. More than 450 of the Met’s 1,700 employees contributed to the exhibition, which is held in the space next to the museum’s ancient Greek sculpture hall, Hyperallergic notes. The show accepts all staff-made submissions, which are installed by Met staff members working extra hours.

Daniel Kershaw, a Met exhibition design manager who has overseen the show’s curation for more than two decades, says he identifies themes that unify the disparate submissions, grouping pieces that work well together (for example, landscapes go next to other landscapes). This year’s show includes a photograph of Cuba, an oil painting of a partially frozen pond, a series on Black life in Brooklyn’s Crown Heights neighborhood, and jars and cans painted to look like tiny monsters, among other works.

Until this year, museum officials and employees were extremely furtive about the exhibition—so much so that the New York Times’ Corey Kilgannon struggled to find sources for a 2012 story on the show. When he visited the Met and asked guards about it, they told him they were forbidden to discuss it with the press.

After some more digging, Kilgannon found a few guards willing to talk, including Peter J. Hoffmeister, who expressed concerns about the secrecy around the event. “It’s complicated to have artists working for you who want their art on the walls—I understand that,” Hoffmeister told the Times. “But as an artist I think it should be public, because keeping it private defeats the purpose of having an art show.”

Some of the Met’s employees are artists who work at the museum to supplement their income, while others make art as a hobby, according to Hyperallergic. But everyone who submits to the show is balancing their art with their day jobs.

Back in 2012, one such individual was Christoper Boynton, a painter, photographer and museum guard. At the time, Boynton didn’t know why the show was closed to the public. “Maybe it’s because they would have to insure the art in the show,” he told the Times. “Maybe it’s that, if someone’s artwork is shown at the museum, people may think it’s being sanctioned by the museum.”

“Art Work: Artists Working at the Met” is on view at the Metropolitan Museum of Art in New York City through June 19.