These fantastically named natural pools look like something out of a Scottish myth.

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

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

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

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

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.

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

A crumbling hospital from the 1850s on Roosevelt Island.

An exquisite tunnel of cascading flowers.

Rippling sand dunes frozen in the Arizona rock.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

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

A psychedelic labyrinth on the San Francisco bay.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

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

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

A huge musical instrument played by the ocean.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

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

The remains of this visionary community can still be found much as it was a century ago.

This grave marks the final resting place of a legendary frontiersman... unless it doesn't.