This concrete ship has had four careers - World War I tanker, floating amusement park, fishing pier, and artificial reef.

Thousands of turbines whir at at the origin of North American wind power.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

The highest point in Nevada had to be decided by court order after California tried to claim it as their own.

Hidden beneath a lake for decades, this brutalist mine has now emerged from beneath the receding waters.

A popular tourist cave with a dark past.

A remote crossroads honoring a fallen talent.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

The tragedy of the Japanese internment camps is remembered here by a stark "Soul Consoling Tower."

A glimpse into the lives of the the Miwok and Paiute people in Yosemite National Park.

The interior of the Overlook Hotel in "The Shining" was based on this Yosemite original.

The first life claimed by this record-breaking peak wasn't lost to exposure or a fall but rather lightning.

A dwindling menagerie of anthropomorphic oil derrick animals still dot the barren California landscape.

Towering basalt columns, a creation of fire and ice.

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

San Francisco's oldest operating hotel, with a Victorian atmosphere and a "haunted" fourth floor.

Inside an old airplane hangar, friends and strangers alike play on a massive trampoline.

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 oldest surviving monument and meeting place for 1906 survivors.

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

A monument to the love people have for their pets.

Radioactivity still cause for concern at this urban explorer's paradise.

Adolph Sutro's little-known, geographically inaccurate, deprecated monument.

A collection of 20th-century automata, penny arcade games, and musical contraptions.