The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The "3rd largest" city in California is an empty mirage of suburbia in the middle of nowhere.

Only intact Ichthyosaur skeleton in the United States.

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

San Francisco Bay's ghost town.

Once connected to the outside world by a single train track, this ghost town is looked after by the National Park Service.

Beyond the usual stories that attend old prisons, this one has deep bloody undercurrents.

A toxic ghost town sitting atop a massive coal fire.

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

The Home and murder site of the witch of Rehmeyers Hollow.

Bizarre Cavern.

Remnants of a storybook amusement park hidden behind a strip mall.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

The United States Capitol's former columns still stand.