Members of campus group Cal Climbing are used to scaling structures throughout California. Now, some of them are doing it naked.

Students sighted some unclothed students climbing on Sather gate Tuesday night — a stunt that turned out to be the final photoshoot for campus group Cal Climbing’s forthcoming nude calendar. The picture will appear on the cover of the calendar, which is set to be sold for $10 on Sproul Plaza and the organization’s website.

“(We thought it was fine) as long as we didn’t get caught in the act,” said Cal Climbing co-President Ben Corbett, noting the campus’s tradition of naked runs through Main Stacks library near the end of each semester. “This is Berkeley.”

So far, the climbers have managed to largely stay out of trouble — except for one instance during a photoshoot around Doe Library, in which a security guard asked them to leave, according to Corbett. They came back later.

Corbett came up with the idea for a nude calendar about three years ago, but he said it took him some time “to convince people to take their clothes off and take photos in the cold.” Some photos featured in the calendar will be up to two years old.

In addition to the photo of the members on Sather Gate and Doe Library, other locations set to appear in the calendar are Indian Rock Park, Salt Point State Park and Bishop, California. The funding of the calendar will go toward trips and gear for the club.

Jessica Lynn is the city news editor. Contact her at [email protected] and follow her on Twitter at @jessicailynn.