Each summer, the migratory bats living beneath the bypass form "batnadoes" at dusk.

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

An overgrown collection of miniature buildings still stand as evidence of one couple's obsession with The King.

This collection of over 50 classic pinball machines awaits visitors to downtown Roanoke.

This Maryland farm is known for its amazing corn mazes and its 30-foot junkbots.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

People escaping slavery may have hidden inside a corpse vault.

The oldest continuously operating fish market in the United States.

A historic neighborhood church is reborn as a psychedelic arts collective.

A derelict bit of transportation infrastructure hidden in the woods.

A wondrous old library overlooking the nation's capital.

A hoard of sky catalogs, astrophysical journals, even the works of Galileo and Copernicus.

Helen Keller once broke ground on this historic center for the study of technologies to benefit the hearing impaired.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

Giftshop catering to cryptozoologists and anyone with a sense of humor.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

When it comes to handsignals (and colonialism) rock always beats scissors.

A computer bug so primitive it was an actual insect.

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

The unique traffic pattern named for an influential urban planner is also known as the Pedestrian Scramble.

There's an old indoor swimming pool hidden directly underneath the White House Press Briefing Room.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

Massive prehistoric mammals used these stones as oversized scratching posts.