An emerald-green grotto just a short trip from Austin.

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

James Turrell's total color immersion art installation, hidden on the top floor of a luxury handbag shop.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

On the Oregon coast there is a natural hole that seems to be draining the sea.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

Most-visited and most-photographed slot canyon in the American Southwest.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

Rippling sand dunes frozen in the Arizona rock.

World's first "penitentiary," meant to be humane, drove men insane.

Non-profit time travel mart sells goods you would need for a trip through the fourth dimension.

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

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

A psychedelic labyrinth on the San Francisco bay.

A terrific purveyor of natural history objects and curios.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

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