Surrounded by traditional homes, this Tolkien-esque dwelling stands out on a quiet street in suburban Maryland.

This ancient market is often referred to as the oldest shopping mall in the world.

One of the oldest living oak trees in the Southeast.

There's an old indoor swimming pool hidden directly underneath the White House Press Briefing Room.

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.

Elevated freight railway turned wildly successful urban park.

This statue of one of baseball’s greatest pitchers looks like something out of a sci-fi horror movie.

The unique traffic pattern named for an influential urban planner is also known as the Pedestrian Scramble.

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

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