Home to a vast and influential collection of Shakespeareana.

The U.S. Navy’s preposterously detailed mini battleship took 77,000 hours to complete.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

Part of a WWII submarine is lurking outside the Washington Navy Yard parking lot.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

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

An overlooked memorial honoring the local Washington residents who died in World War I.

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

Every drop of D.C. tap water flows through this old waterworks.

A building shaped like the Army Corps of Engineers logo, because why not?

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

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

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

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

Senators used to relax in the nearly forgotten marble tubs now hidden in the U.S. Capitol Building's basement.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

A diminutive plaque recalls the treetop sniper who almost killed Abe Lincoln.

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

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

The discovery site of the "Capitalsaurus," the official dinosaur of Washington, D.C.

One of the largest artillery pieces in the world sits in a Washington D.C. parking lot.

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

This unacceptably tall building was the real reason for Washington, D.C.'s skyscraper ban.

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