It was once the base for a series of domestic terror attacks.

A much-maligned monument to teetotalism.

The fountains of the U.S. Navy Memorial are annually salted with water from the Seven Seas as part of a nautical ritual.

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

Perhaps the most scandalous statue of America's first president.

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

Home to items never before seen by the public.

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

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

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

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

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

This massive swimming pool is the high tech home to the human-powered submarine races.

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.

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

On the Fourth of July this area will transform into a Pompeii-like storm of falling embers and ash.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

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

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

Decades before the scandal, this staircase on the river was a literal "water gate."

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

A line of blue paint marks the route of the inaugural parade.

The bank that helped fund the Mexican-American War and the purchase of Alaska met its downfall after helping Augusto Pinochet launder money.