Furniture tries to escape an abandoned building in San Francisco.

A shining, cold, black organ lies in San Francisco's financial district.

Only hotel where you can legally launder money.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

One of the oldest producers of hand-folded fortune cookies still uses its original secret recipe.

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

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

The miraculous hydrant that saved the Mission District in 1906.

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

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

A 300-ship graveyard, with a few still visible at low tide.

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

A museum befitting the city responsible for supplying the majority of the world's LSD.

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

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

A magnificent, reportedly haunted mansion built for a composer by Spiritualists.

A working miniature city designed to teach kids about safety and presumably city planning.

The longest burning light bulb in the world.

A ruined hotel with an unlucky history and an eerie present.

This hidden amusement park is a magical escape for kids and kids-at-heart.

This former luxury resort in Kaua'i is now an abandoned relic.

A Hawaiian stairway to heaven—that you can't climb.

A unique set of caves that spits waves back out into the ocean.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.