Found art has transformed this Pittsburgh neighborhood into a psychedelic dream.

These banned cigarette vending machines now sell little pieces of pocket-sized art.

An inconspicuous footbridge beloved by San Diego locals.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

An abandoned stretch of highway, deteriorating next to the operational one.

Home to the infamous "Typhoid Mary" and the worst loss of life in New York's history prior to September 11, 2001.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

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

A beautiful oddities shop crammed with strange and morbid curiosities.

A bizarre roadside attraction and the first instance of miniature golf in the world.

Nondescript elevator doors open to reveal a stunning, surreal world.

Tucked in a nondescript downtown Brooklyn mall is a bar containing a remarkable turn of the century anatomical wax collection last seen in 1920s Berlin.

A century-old hotspot for jazz, frequented by everyone from Charlie Chaplin to Al Capone.

A shop full of natural curiosities, carnivorous plants, and costumed taxidermied mice.

The longest navigable underground river in the United States is home to countless blind and albino animals.

An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

Ruins of the elaborate house where the enigmatic costume designer threw glamorous parties for New York's theatrical elite.

A tiny red pebble marks what may be the quietest outdoor spot in the United States.

A colorful architectural gem in Seattle's uniquely modern Central Library.

The largest earthwork effigy in the world.

Crammed into a Baltimore row house is an oddities shop that sells everything from skulls to dead insects.

The scuba diving training facility was named for the steam that rises from the cave's chimney.

Rare recess caves fill this unbelievably beautiful Ohio park.

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