Big gun installations, built over a massive cemetery, now abandoned & hidden in trees.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

A modern mechanical planetary system, part of a 10,000 year clock.

Visible below the waves are memorials to the city's Gold Rush dead.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

An essential stop before plundering, BYO Cutlass.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

A shop full of natural curiosities, carnivorous plants, and costumed taxidermied mice.

San Francisco's newly reopened hands-on science museum.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Olfactory delights in San Francisco's Botanical Gardens.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

The only theatre in the world constructed specifically for sound movement.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

A psychedelic labyrinth on the San Francisco bay.

A huge musical instrument played by the ocean.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.