When it was built in 1929, this historic bridge was the only place to cross the Colorado River for 600 miles.

Once a sewer culvert, this road tunnel now offers cyclists and pedestrians a subterranean stroll under the C&O Canal.

At night, a grove of towering redwood trees growing through the pavement block out all light from the so-called “Dark Park” of Madrone Avenue.

Fifty years after a “blast blasted blubber beyond all believable bounds,” this idyllic natural area commemorates the carnage.

Spiral labyrinth hidden in the hills above Oakland, CA.

This peaceful garden is hidden on the grounds of a spiritual organization founded by a pioneer yogi.

A modern frieze of ancient Grecian mythological figures playing a national pastime.

A tribute to the pop culture icon overlooks this Washington D.C. intersection.

Located near Cairo's El Korba district, the abandoned mansion continues to inspire mystery and rumor throughout the city.

Sacred Buddhist home of some spiritual monkeys.

An extensive collection of ancient Egyptian artifacts and mummies.

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

A man-made island in scenic San Francisco Bay.

Deco Modern sculptures of the people of the Pacific, cast for the 1939 Golden Gate International Exposition.

This Oakland fairytale kingdom, fiercely devoted to childlike whimsy, was an early inspiration for Disneyland.

With statues of Nelson Mandela and Harvey Milk this monument has been called the Mount Rushmore of California.

9,000 square feet of vintage and modern mechanical toys, dioramas & sideshow curiosities.

Handmade treasures from around the world.

Where the alchemists dream of transmuting base metal into gold was actually achieved.

The century-old bell and clock tower at UC Berkeley is the third-tallest in the world, and has fossils.

A shape-shifting buy-sell-trade bookstore, born to Beatnik Era spirit.

This subtle Berkeley paving stone actually marks off a lawless tube of air that extends into space.

The only museum of sake in the United States is nestled in an unlikely California college town.

A 90-acre park on former landfill that hosts an annual kite festival.