A burnt orange monolithic dome structure perched on a hillside near Interstate 280.

San Francisco's newly reopened hands-on science museum.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

A man-made island in scenic San Francisco Bay.

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

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

Guns that have been defending San Francisco since 1904.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

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

A garden oasis filled with flowers mentioned in the works of William Shakespeare.

San Francisco's first World's Fair, dedicated to the wonders of California.

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

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

Once the largest windmill outside of Holland, with enormous 114 foot sails.

The most beautiful Taco Bell in the world even has surfboard parking.

The graffiti-covered remnants of a former triangulation station are balanced precariously on this California peak.

This controversial depiction of the "Founder of California" looks as though it was sculpted from mashed potatoes.

A 1920s speakeasy that had rum runners racing up and down the shores of California.

This old-world mansion with lush gardens is a gem in the heart of Silicon Valley.

Once close to extinction, there is no shortage of elephant seals on the beaches of Año Nuevo State Park.

Here, visitors can swing with the waves of the Pacific Ocean.

A gathering of green robots at the Googleplex.

From the Difference Engine to the Cray-1, all under one roof.