This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

The fairy tale castle of the "fairy-tale king."

Try not to get slimed in Tribeca.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

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

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

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.