A collection of memorabilia from the Beat era in the back of a San Francisco bookstore.

Golden Gate Park's historic collection of plants.

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

A modern mechanical planetary system, part of a 10,000 year clock.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

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

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

A winding path built in secret on the edge of the continent.

The only theatre in the world constructed specifically for sound movement.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

A psychedelic labyrinth on the San Francisco bay.

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

An artsy hidden staircase leads to breathtaking views of San Francisco.

A huge musical instrument played by the ocean.

Big gun installations, built over a massive cemetery, now abandoned & hidden in trees.

A statue in the Texas town that proudly calls itself the killer bee capital of the world.

This mountain tram provides stunning views while hanging from a single, steel thread.

A wacky, UFO-shaped house in a suburban neighborhood.

This tiny, hurricane-resistant house in Galveston is one of the city's most notable architectural oddities.

In Paris, Texas, even Jesus wears cowboy boots.

These half-buried combine harvesters just off Route 66 are an homage to the Cadillac Ranch.