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

A humble garage, world-famous for being the epicenter of a technology revolution.

This odd California folly seems like it was almost designed to accumulate urban legends.

A hidden world of exotic succulents and cacti.

A lonely monument to the original Silicon Valley tech campus.

Three plaques mark the spot where the "forgotten father of broadcasting" worked.

For roadside fast food, pull over at the giant orange.

San Francisco Bay's ghost town.

The grand, column-fronted, sculpture-adorned home of the ambitious digital library.

A modern mechanical planetary system, part of a 10,000 year clock.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

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

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

The only theatre in the world constructed specifically for sound movement.

Tiki luxury on Nob Hill.

A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

A 140-year-old castle with underground caves hidden in San Francisco.

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

A huge musical instrument played by the ocean.

Frank Lloyd Wright died a year before construction on his largest public project even began.

George Lucas donated this park to honor the birthplace of his two biggest movie franchises.