Winters in the Windy City are notoriously long, but the Art Institute of Chicago gave visitors an unexpected dose of the cold this summer: a frozen sculpture of a snowman atop the museum’s terrace, basking in the hot sun.

The piece, simply titled Snowman, is the work of Swiss duo Peter Fischli and David Weiss and was first conceived in 1990, as a commission for Saarbrücken, Germany. “They were looking for a piece for in front of a power plant. We decided it had to be something that was dependent on the power of the power plant,” Fischli told the New Yorker. (Weiss died from cancer in 2012.)

Peter Fischli and David Weiss, Snowman. Courtesy of Oskar Weiss.

Locked away in a six-and-a-half-foot-tall vitrine, with a long extension cord plugged into the wall, the encased snowman is not actually made of snow but is instead a frost-coated copper sculpture filled with water. The box is kept quite humid, and within a few days, condensed water collects on the surface of the statue and freezes, transforming the work into a wintery figure.

Every morning, the display gets a new batch of distilled water, and the snowman’s smile is reshaped. The frosted glass comes courtesy of a fine mist of water spraying inside the tank.

Peter Fischli and David Weiss, Snowman at the Art Institute of Chicago. Courtesy of the Art Institute of Chicago.

With their carefully maintained air conditioning systems, art museums are a great way to beat the summer heat, but a snowman is still quite the unexpected spectacle—and that’s by design. The incongruous sight is meant to “confuse hierarchies and values by creating systems doomed to fail,” the museum told DNA Info. Unsurprisingly, the piece has become a popular selfie spot at the institute.

Following the exhibition’s end next month, Snowman will travel to the San Francisco Museum of Modern Art and the Museum of Modern Art in New York.

Peter Fischli and David Weiss, Snowman at the Art Institute of Chicago. Courtesy of Oskar Weiss.

“Fischli/Weiss: Snowman” is on view at the Art Institute of Chicago, 111 South Michigan Avenue, April 27–October 2017.