The graffiti-covered remnants of a former triangulation station are balanced precariously on this California peak.

Abortion, prohibition, religion, war, and fear all play a part in the history of this idiosyncratic Pacifica castle.

The world’s first stop-motion film was created on the racetrack outside this building.

The Internet Age began with a transmission from this biker bar.

This small monument to the great inventor contains a time capsule and a Wi-Fi hotspot.

This odd California folly seems like it was almost designed to accumulate urban legends.

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

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

One of the largest free-standing structures ever built, this dirigible hangar is now simply a giant skeleton.

Since 1973, this block has been home to the most concentrated collection of murals in San Francisco.

A decommissioned Naval base now rents itself out for people who want to blow stuff up.

Sitting atop San Francisco's tallest hill, a cross honors the victims of the Armenian genocide.

A miniature view of the park, caught in time.

A winding path built in secret on the edge of the continent.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

Adolph Sutro's little-known, geographically inaccurate, deprecated monument.

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

A 300-ship graveyard, with a few still visible at low tide.

Alleyway plaque commemorating the death of a fictional character in The Maltese Falcon, not far from the author's home.

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

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

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

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

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