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

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

A mysterious monument covered in a binary code marks the heart of tech.

San Francisco Bay's ghost town.

This 19th-century church is now a popular roller rink.

A walk down memory lane in the heart of one of San Francisco's most notorious neighborhoods.

Spiral labyrinth hidden in the hills above Oakland, CA.

The oldest burial ground in the city, final resting place of city founders, Ohlone natives and murderers alike.

Oakland's beautiful monumental cemetery.

Julia Morgan's Moorish-Gothic labyrinth of fountains, trees, natural light and Oakland's notable dead.

This one-block alleyway is stuffed with street art that is colorful, cultural, and intensely political.

Tenacious mummies survived dental problems, eternal entombment, and more than their fair share of devastating fires.

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

A temple devoted to inner esoteric mysteries located in a California commercial strip.

A rough granite monument marks the spot where Europeans first caught sight of the San Francisco Bay.

The memorial to the victims of the Jonestown Massacre carries the names of 918 lost, including one name people wish wasn't there.

Housed in a memorial lighthouse, this museum relays the history of surfing, beginning with the antics of royal Hawaiian teenagers.

A unique piece of graffiti offers a little slice of local history and mystery.

Neoclassical Revival mansion and set of horror cult classic Phantasm.

Elephant seals and sea lions have turned the abandoned buildings on this island into their endangered love shack.

A Roman-inspired temple once controlled half of San Francisco's waters.

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

A trail weaves through the verses of a poem illustrated by stone sculptures inspired by Native American pictographs.

A sudden forest of traditional Papua New Guinean art works is hidden in a corner of Stanford University.