An eerie, decaying ghost town destined to fade into the forest.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

This sci-fi gazebo located in a Washington power town is made from old bits of industrial electrical equipment.

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

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

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

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

Corn-inthian columns with a uniquely American take on neoclassical architecture.

An ear-piercing buzzer calls lawmakers to a vote with a series of long and short rings to form coded messages.

After his presidency, George Washington planned to live only a few blocks from the Capitol building.

A surprising, but overlooked example of geology in the middle of the nation’s capital.

D.C. once had its own tiny rival to the New York Stock Exchange.

This statue of the "father of television" stands prominently in the United States Capitol.

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

The tunnel under the Capitol Building where Congress takes out its trash.

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

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

Go take a picture with the inventor of the daguerreotype photographic process.

The towering figures were created from the cemetery's fallen old-growth trees.

This poor little statue is the most vandalized memorial in Washington.

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

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

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

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”