This concrete ship has had four careers - World War I tanker, floating amusement park, fishing pier, and artificial reef.

An ominous concrete cube cuts a dystopian silhouette atop this California mountain.

This giant shopping mall still holds signs of its automotive past.

A giant chess set, minus the psychedelic drug trip.

The headquarters of a secretive order is also a beautifully-designed park.

An extensive collection of ancient Egyptian artifacts and mummies.

The largest permanent Monopoly board makes one of the longest games even bigger.

A statue commemorate Tommie Smith and John Carlos's brave protest at the 1968 Olympics, a watershed moment for civil rights.

A century and a half of research in the sciences and natural history, still going strong.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

A still functioning vaudeville carousel that has operated for over a century boasts a colorful menagerie and past.

Furniture tries to escape an abandoned building in San Francisco.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

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

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

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

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

Concrete strongholds stand guard over the Golden Gate.

A pair of pure white felines guard the entrance to a spot of California real estate established as an artist's haven.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

The most famous location in China was home to whole dynasties worth of imperial rulers.