This Boston medical museum features the skull of the famous medical case of Phineas Gage.

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

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

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

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

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

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

New York's oldest magic store.

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

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

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

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

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

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

The legendary building that needed ghostly approval before being built.

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

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

Dramatic river bend surrounds a natural red-rocked pedestal.

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

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

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

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

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.