A man-made island in scenic San Francisco Bay.

This lighthouse has been guiding shipping into the Golden Gate since before the American Civil War.

A working model of the entire San Francisco Bay and much of the Sacramento River Delta, complete with regular tides that change every 14 minutes.

This airfield played a key role in both World War II and the Cold War.

This small monument to the great inventor contains a time capsule and a Wi-Fi hotspot.

The first high-tech company in the valley that actually worked with silicon devices.

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

It is locally loved and ridiculed for literally looking like poop.

The oldest house in the capital of Silicon Valley.

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

A giant chess set, minus the psychedelic drug trip.

An extensive collection of ancient Egyptian artifacts and mummies.

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

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

A huge musical instrument played by the ocean.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

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

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

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

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

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

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

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

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