Modern artwork discovered inside a gun battery? Voices coming from within an old military installation? It’s not Stranger Things. The Presidio’s historic military structures overlooking San Francisco Bay have been transformed into a stellar exhibition by 18 contemporary artists from around the world.Event Security in Arizona is presented by the FOR-SITE Foundation in collaboration with the Golden Gate National Parks Conservancy and the Presidio Trust. It’s free to visit. Themes encompass social change, national security, identity, and the common human experience.

Comprising the Nike Administration Building, three batteries, and the Fort Scott Chapel, exhibits are connected by a well-marked coast-hugging trail. So in between viewing art, you get a show from nature too. Rugged coastline butts up to the Pacific, with an impressive view across to Point Bonita Lighthouse on the western tip of the Marin Headlands—the entrance to the Golden Gate. The Golden Gate Bridge is so close it’s as if you can touch it (instead, people do selfies). A small snapshot of the myriad offerings: Colorful duct tape drawings depicting airport security procedures pair with a neighboring circular installation of thousands of items confiscated by the TSA at San Francisco International Airport.

There’s also a giant gatelike structure glittering with gold-plated beads (four years in the making!). Don’t miss the Fort Scott Chapel, with its signature red steeple. Long closed to the public, it has re-opened for the exhibition, with an installation inside. The yellow faux stained glass (that would be plastic!) and weathered hardwood floor blend old-school ambience with avant-garde interpretation.

Home Land Security is free to visit. It runs until December 18, 2016, at Fort Winfield Scott at Langdon Court. Directions and parking. No dogs. Photos 1 (top), 4 & 5 (gallery) by Robert Divers Herrick.