The longest navigable underground river in the United States is home to countless blind and albino animals.

A fleet of automotive automatons sleep in this otherwise unremarkable urban garage.

A spiritual center in the Santa Monica Mountains founded by Alice Coltrane after the death of her husband and fellow jazz musician John Coltrane.

Factory that once supported an entire company town of 350.

Decommissioned experimental solar facilities that pioneered solar energy technology.

The mysterious, untimely death of a Canned Heat band member still haunts this unfinished home.

Rusty industrial city full of oxidized distillation towers.

A black and white painted wall creates an optical illusion in the California desert.

Abandoned in 2009, this once popular resort destination now stands frozen in time.

An Old West film set seen in countless TV shows and movies is open for the public to explore.

Floating man-made island and upscale restaurant.

This enormous World War II relic is one of the largest wooden structures in the world.

An abandoned, unfinished mansion on grounds strewn with lava rocks.

A rococo retro-futurist future-rustic vernacular between yesterday’s tomorrow and the future that never was.

Secret Manor, a house full of legends, the least of which is the haunting of long-deceased ladies of pleasure.

Furniture tries to escape an abandoned building in San Francisco.

The old Niles Canyon Aqueduct in the San Francisco Bay Area is a bemusing and secret trail through nature for wayward travelers.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

This vast and otherworldly landscape is one of the largest dune complexes in North America.

An abandoned early 20th-century gold mine in a spectacular setting overlooking Bridgeport Valley and the Sierra Nevada.

Visit a remnant California's Gold Rush, which locals claim is haunted by spirits from the past.

Sporting Brutalist architecture, this school is hidden amid a quiet suburban neighborhood.

A little-known, but surprisingly large waterfall on the Little Truckee River in the northern Sierra Nevada.

A mine in the Sierra Nevada that produced nothing but barren quartz.