A diminutive memorial marks the site of a successful assassination by a right-wing death squad in America's capital.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

An abandoned stretch of highway, deteriorating next to the operational one.

Granite outcropping that the state's tourism bureau doesn't promote because of its delicate ecosystem.

A historic ruin just 20 feet away from a busy highway onramp.

A Spiritualist house of worship where believers communicate with the dead in the spirit world.

Before Nixon, "watergate" meant canals.

Decades before the scandal, this staircase on the river was a literal "water gate."

The hidden offices underneath Memorial Bridge have been locked up since 1976.

A unique workspace where offices reside on pirate ships and inside gingerbread houses.

The span is crooked and made from two older recycled bridges.

A former major munitions plant that has been converted into a sprawling art space.

Rowdy rebels fortified this home during the first popular uprising in United States history.

Built by the patriotic residents of Boonsboro in a single day.

A rapidly disappearing authentic bit of the old south.

Better known as the "Body Farm," this unique research facility has been studying how human bodies break down since the 1980s.

This improbable contraption was passed down through five generations of industrious Tennesseans.

An occult-y, historic hotel with the World's Largest Ouija board on the roof.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

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

The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

Also known as the Founding Church of Scientology.