This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.

A Texas-sized particle collider that was abandoned due to its Texas-sized budget.

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

Home to items never before seen by the public.

At 207 feet, one of the world's longest continuous escalators.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

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

Mysterious stone tower featured in many alternative histories of the New World.

This lighthouse was witness to the end of WWII hostilities and now collects creepy cairns.

250-year-old farm now features sculptures, a petting zoo and a hippy-bazaar.

Ironically this massive termite is the mascot for a company that is acclaimed for killing his kind.

An architectural statement of artistic intent smack in the middle of Providence, Rhode Island's Colonial uniformity.

The world's tallest statue of an American hero.

Resting place of the Texas A&M canine mascots, who watch the game from the grave with their own miniature scoreboard.

Circus cemetery for all the “showmen under God’s big top.”

Housed in a century-old building, this museum's dedicated not just to soft drinks, but to the free enterprise system.

Official museum, hall of fame, and repository of the Texas Rangers.

Tracks near this Texas nature site were once thought to support the Creationist belief that man and dino coexisted.

A small "palace" and museum made of, and devoted entirely, to salt.

A Texas museum filled with Broncos and Betties.

A modernist landscape of water and sci-fi concrete.