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

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

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

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

An obscure public service from the U.S. government that redeems burnt, moldy, and soiled old greenbacks.

The oldest continuously operating fish market in the United States.

The only National Monument ever to go missing for nearly 50 years then resurface in a dump.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

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

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

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

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

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

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.

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

The National Park Service’s best-kept secret with views that rival any in D.C.

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

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

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

The preamble to the U.S. Constitution written entirely from vanity license plates hangs in the Smithsonian museum.

Light bulbs, scrap wood, and tinfoil comprise this homemade throne of the gods.

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

A historic ruin just 20 feet away from a busy highway onramp.