The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

This historic tower in the California desert promises visitors a "vortex of good vibes".

This immigrant bridge once spanned the Thames but is now a fixture of an Arizona city.

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

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

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

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

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.

A man-made island in scenic San Francisco Bay.

A huge musical instrument played by the ocean.

The only visible piece of San Francisco's most famous shipwreck.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

Forgotten and then destroyed by fire, this was once one of the largest saltwater swimming pools in the world.

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

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

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

Furniture tries to escape an abandoned building in San Francisco.

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

A New England-style lighthouse along California's beautiful Highway 1 gets a re-do.

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

Historical trolley restoration and operation at History San Jose, Kelly Park.

From the sky, a kaleidoscope of color brightens the grey landscape of the San Francisco Bay.

The largest permanent Monopoly board makes one of the longest games even bigger.