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

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

A pier that used to act as a busy ferry dock is now a decaying favorite of local fisherman and urban artists.

Once the largest winery in the world, this castle-like building now sits abandoned on the San Pablo/San Francisco Bay shore.

The rusting remains of the largest assembled WWII fleet on the West Coast.

An abandoned convention space that has been left to the homeless and the radical.

This mountaintop beacon is only lit three times a year but shines like some kind of all-seeing eye.

Another of California's unused Cold War missile defense complexes has become a graffiti gallery.

Built by the inventor of the radio, this abandoned hotel has housed early radio employees, military men, and a dangerous cult.

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

Before it was abandoned and left to rust alongside the road, this riverboat starred in a John Wayne movie.

An abandoned Cold War missile radar site.

An abandoned car and strange wooden debris are among the scattered remains of the old sand and gravel quarry.