This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

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

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

Parking garage where Bob Woodward met Watergate source "Deep Throat."

Home to items never before seen by the public.

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

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

Washington's iconic carousel has a nice piece of Civil Rights history.

The most decorated dog of World War I is preserved in the Smithsonian.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

Look closely and you’ll notice that the color changes a third of the way up the tower.

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

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

The oldest continuously operating fish market in the United States.

There’s a hidden military meme engraved on the World War II Memorial.

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

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

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The national park was once a plantation estate.

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

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

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

Rumor has it the hot dog stand was targeted by two Russian nuclear missiles.

The controversial urban planner who designed Washington, D.C., was buried in Maryland, and can presently be found in Virginia.