These Pre-Columbian petroglyphs contain representations of birds, deer, hunters, and even some early Native flute players.

Here, at the "world's longest art gallery," you'll find forty miles of ancient petroglyphs and pictographs.

"The country that ate itself."

This nearly abandoned plantation was once witness to an eclipse that proved Einstein's theory of relativity.

Nature’s skyscraper launches out of the terrain with attitude.

The ship that got left behind.

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

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

The seamy, underground secrets of Portland's criminal past.

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

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

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

Rippling sand dunes frozen in the Arizona rock.

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

A toxic ghost town sitting atop a massive coal fire.

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

A church of bones, decorated with 40,000 human skeletons.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

A beautiful, dense forest in the shadow of Mount Fuji, with a tragic reputation.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

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

The vast, legendary catacombs hold secrets much stranger than stacked bones.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.