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.

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

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

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.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

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

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

Fittingly, America's museum of architecture is itself a magnificently designed old building.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

A historic arena where the Beatles played their first concert in the U.S.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.

The national park was once a plantation estate.

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

A much-maligned monument to teetotalism.

‘Bush the old fire dog died of poison July 5th, 1869. RIP.’

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

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

The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

The United States Capitol's former columns still stand.