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

Prone to disastrous fires, the city of San Francisco has the Guardian, a fireboat gifted by residents, to watch over them from the bay.

A man-made island in scenic San Francisco Bay.

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

The remains of a deserted steamboat sit rusting beside an old ferry pier and an abandoned train platform.

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

An Aladdin's cave of old Silicon Valley tech.

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

The rusting remains of the largest assembled WWII fleet on the West Coast.

An vast warehouse of everyday treasures in Berkeley, CA.

After serving in World War II and picking up Apollo astronauts, this aircraft carrier has been turned into a museum overlooking the San Francisco Bay.

A decommissioned Naval base now rents itself out for people who want to blow stuff up.

San Francisco Bay's ghost town.

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

Odd stone and concrete monuments in the "Poet of the Sierras" eclectic folly garden.

Thousands of crosses and markers for soldiers who lost their lives in Iraq and Afghanistan blanket a California hillside.