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

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

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

The early data processor factory founded in Washington for the 1890 U.S. Census went on to become IBM.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

The site of the climactic scene from the classic horror film is now a historic landmark.

Before Metro, Washington had a robust streetcar network—and you see the remains of this infrastructure if you know where to look.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

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

The national park was once a plantation estate.

This church built atop a gas station promises to "equip you for the next stage in your life’s journey."

This unique historical monument features large concrete spheres designed to resemble fallen stars.