A line of blue paint marks the route of the inaugural parade.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

The remains of a historic plantation nestled in between a parking lot and the rental car return at Reagan National Airport.

Rumor has it the hot dog stand was targeted by two Russian nuclear missiles.

This rare triple-jurisdiction drawbridge passes through Virginia, Maryland, and Washington, D.C.

She stares out across six lanes of traffic, clutching a musket and infant with determination.

A painfully obvious spy house sits right across the street from the Russian Embassy.

A derelict bit of transportation infrastructure hidden in the woods.

This simple stone memorial remembers a secret, Geneva Convention-defying interrogation base from WWII.

The school tested mustard gas for the U.S. Army during World War I.

The romance of early commercial flight still fills this Art Deco destination.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Despite time, colonization, and the brutal New Mexican heat, these Pueblo ruins still stand.

A sprawling collection of over 106,000 toys from around the world.

These Pre-Columbian petroglyphs contain representations of birds, deer, hunters, and even some early Native flute players.

This southwest-styled home in Santa Fe claims to be the oldest house in America thanks to an ancient bit of foundation.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

This innocuous New Mexico storefront was once the secret jump-off spot for Manhattan Project scientists.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

This pun was simply waiting to come to life, and one defense contractor made it so.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

Washington's top-secret Cold War-era doomsday communications tower is located in a small neighborhood park.