Where hills of dirt conceal the burial ground of one of the most powerful ancient Native American societies.

A peculiar forest that was handcrafted for government experiments.

Collection of skeletal systems from the "world's leading supplier of osteological specimens."

Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

Tucked away on an empty wooded lot in suburban Oklahoma City lie the remnants of an abandoned circus camp.

A larger-than-life monument to the overlooked women who braved Western expansion and broke down societal barriers.

This highway overpass was named after the tragic disappearance of a young mother who got mixed up with the wrong people.

An abandoned subway tunnel that could have reinvigorated Staten Island still lies somewhere beneath this Brooklyn park.

Where America's first doomsday cult awaited the end of the world.

The abandoned coal loading dock is a canvas for unsanctioned art.

This hospital fell into ruins after failing to act as the advocate for the mentally ill it was designed to be.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

This empty Victorian manse on Staten Island is said to be haunted but is actually a real life crime scene.

This tiny New Jersey village has lived many lives but seems determined to remain a ghost town.

The headquarters of the Fraternitas Rosae Crucis, complete with Rosicrucian pyramids, all in the Pennsylvania woods.

This Philly landmark has a giant butterfly pavilion, three floors of insect displays, and withstood a $40,000 heist.

A recently abandoned psych ward at the end of Sanatorium Road.