This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.

This funicular railway rumbles along for a mile up the nearly vertical face of Chattanooga’s Lookout Mountain.

This handcrafted, old western-style town is filled with deserted cars, retired movie props, and other forms of Americana.

From failed port town to Civil War fort, the ruins of this former defense saw their finest day in the television age.

Garden dedicated to native carnivorous plants and site of huge flytrap heist.

A curious collection of oddities including a lock of Alexander Hamilton's hair and Harry Houdini's ouija board.

More than five miles of underground passageways.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

This historic train station has been converted to a locomotive themed hotel.

This set of rickety spaceships are prepared to give alien travelers a place to relax and go to the bathroom.

A railroad tunnel that, upon its completion, was considered one of the engineering marvels of the modern world.

The ruins of this Thomas-Jefferson-designed mansion have been left to crumble since the Christmas Day they burnt down.

Hidden for 165 years inside a building designed by Thomas Jefferson are the remains of what may be America's first educational chemistry lab.

Edgar Allan Poe's old dorm is now a shrine to the author's legacy.

Outdoor exhibits explore the contributions of European, African, and indigenous peoples to American frontier culture.

Herbert Hoover's "Brown House" rural presidential retreat was a PR disaster amid the start of the Great Depression.

A former mental hospital founded in the 1930s by a eugenicist who advocated for the forced sterilization of patients.

One of the last active volcanoes on the Eastern seaboard.

The Avenue of Mausolea is a series of grand palatial tombs.

The site of the climactic scene from the classic horror film is now a historic landmark.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

A cave on the Maryland border where civilians took refuge during the bloodiest battle of the Civil War.