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

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

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

The world's only museum devoted to the wonders of fluorescence.

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

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

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

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

An exquisite tunnel of cascading flowers.

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

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

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

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

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

A snapshot of the city's fascinating voodoo culture.

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

An eerie, derelict amusement park in Berlin.

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.

A magical place that lets you play in and explore the world of Studio Ghibli.

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

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

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

Rippling sand dunes frozen in the Arizona rock.