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

A miniature rainforest is growing inside of a Midtown Manhattan office building.

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

America's most famous piece of self-built architecture.

A trash dump made beautiful by nature's power.

The ghostly remains of an accidental sea.

A layered tribute to the work of mosaicist Isaiah Zagar.

Elevated freight railway turned wildly successful urban park.

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

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

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

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

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

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

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

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

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

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

A one-of-a-kind collection of a unique medium.

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

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

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

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

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