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

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.

Once America’s most beautiful army base, this abandoned military fort on the coast of Monterey Bay has been left to the elements.

Offering commanding views of the California coastline, this restaurant was a hub for the artists and bohemians of Big Sur.

Barely visible foundations remain where Stow Lake’s “observatory” once welcomed visitors.

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

A shape-shifting buy-sell-trade bookstore, born to Beatnik Era spirit.

Every year, over 25,000 monarchs overwinter in Pacific Grove.

A famous alternative culture epicenter and where Joplin serenaded young hippies.

At 207 feet, one of the world's longest continuous escalators.

This Oakland fairytale kingdom, fiercely devoted to childlike whimsy, was an early inspiration for Disneyland.

A vast city of the dead, where the deceased outnumber the living by more than a million.

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

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

The lighthouse central to the 1980s horror classic "The Fog" is, in fact, located in one of the foggiest areas of the Pacific Coast.

A man-made island in scenic San Francisco Bay.

This offbeat trailer park is home to vintage peddlers, local artists, indie makers, and more.

The remains of a 12th-century chapter house in Golden Gate Park.

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

Since 1973, this block has been home to the most concentrated collection of murals in San Francisco.

The national park was once a plantation estate.

The fossilized remains of ancient California redwoods.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

A monument to the love people have for their pets.