The first museum in the U.S. to address human rights issues in China.

A brass and marble scale model of the solar system embedded in the concrete.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

This apartment building designed by a notable Washington D.C. architect housed the Qing Dynasty's Legation.

A portal into the bricked up canal that runs through the heart of Washington D.C.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

An overlooked tribute to one of the most important peace deals in American history.

This bridge over D.C.'s Rock Creek Park is sometimes called the "Buffalo Bridge" because of its four buffalo sculptures, which were cast from a single piece of bronze.

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

A terrace reminiscent of Rome's Spanish Steps is tucked away in a little park in Washington, D.C.

A public art jibe at one of the United States’ oldest and longest-serving senators.

The oldest house in Washington, D.C. wasn't originally constructed in the nation's capital.

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

People escaping slavery may have hidden inside a corpse vault.

This robust fence in front of a historic Georgetown home is likely made from hundreds of recycled Revolutionary War firearms.

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

This small hilltop church weaves the urban history of Washington, D.C. with the national history of the United States.

This fertility idol of questionable authenticity inspired an iconic Indiana Jones artifact.

A memorial dedicated to a highly decorated Marine and Korean War veteran, who also happened to be a horse.

This site is believed to be connected to the oldest house in Arlington County.

The Pentagon sits on a former island that was in Virginia at low tide and D.C. at high tide.

Please don’t anchor your boat onto the Department of Defense’s underwater data cables.

Right next to departures—how convenient!

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