One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

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

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

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

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

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

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

A 140-year-old castle with underground caves hidden in San Francisco.

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

An enormous, inside-out glass globe built in 1935.

Dramatic river bend surrounds a natural red-rocked pedestal.

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

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

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

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

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

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

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

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

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

Rippling sand dunes frozen in the Arizona rock.