Enormous lake at the bottom of a unique cave system.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

The rocks in this arid basin leave trails of movement behind them.

A giant Troll lurks under one of Seattle's oldest bridges.

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

A trash dump made beautiful by nature's power.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

A walk through the historic city center, under the streets of Seattle.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

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

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

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

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

It should come as no surprise that the best view of the Hollywood sign is from Batman's lair.

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

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

Hot springs monkey spa in the middle of Hell's Valley.

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

Medicinal spa created with the discharge from a geothermal energy plant.

Dramatic river bend surrounds a natural red-rocked pedestal.

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

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.