A creepy steel gremlin has protected the Bay Bridge since 1989.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

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

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

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

From the sky, a kaleidoscope of color brightens the grey landscape of the San Francisco Bay.

The world's first permanently occupied mountain-top observatory continues to report on the stars.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A giant chess set, minus the psychedelic drug trip.

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

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.

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

The old Route 66 town straddling Texas and New Mexico died along with the Main Street of America.

This water tower slanted at an uncomfortable angle off the old Route 66 was an ingenious marketing ploy.

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

An immersive art experience built by local arts collaborative, Factory Obscura, in the building formerly known as The Womb, a psychedelic arts center founded by the frontman of the Flaming Lips.

Fresh wooden posts have been added to ancient holes to recreate a primitive henge clock.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

A Nessie-like monster supposedly lurks in this lake.

Formerly the most gerrymandered district in the U.S., it twisted and turned along racial borders.

This set of rickety spaceships are prepared to give alien travelers a place to relax and go to the bathroom.

This quirky curiosity shop takes its cues from the world's bazaars.