Rippling sand dunes frozen in the Arizona rock.

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

World's largest collection of serial killer artwork and other macabre exhibits.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

A huge musical instrument played by the ocean.

Despite the ever pressing encroachment of urban sprawl this grand New Orleans manse still stands.

Trails through lava-carved tube-caves display sparkling bacteria and a rich history.

The restaurant keeps a hidden séance room on the second floor and reserves a table for the spirit of the former owner each night.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

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

This charmingly homemade amusement park has been growing for 40 years.

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

Featuring a casually threatening atmosphere along with dessert and coffee to die for.

Couple's personal collection of pinball machines turned public pinball museum.

A little piece of the Shire is hidden behind a plant nursery in Port Orchard, Washington.

Sniff the Titan Arum's rotting flesh.

An abandoned castle owned and ignored by Masons carries a cursed history.

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

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

A mysterious castle built as a monument to lost love.

Private collection of art inspired by cabinets of curiosity.

This quirky curiosity shop takes its cues from the world's bazaars.