This unique museum cafeteria showcases the history and regional diversity of African American cuisine.

Largest Roman Catholic church in North America.

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

This nine-story building is the oldest standing skyscraper in D.C.

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

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

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

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

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

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

The grand marble structure next to the White House is Andrew Carnegie's temple to Pan-American diplomacy.

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

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

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

Before Nixon, "watergate" meant canals.

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

Helen Keller once broke ground on this historic center for the study of technologies to benefit the hearing impaired.

The early data processor factory founded in Washington for the 1890 U.S. Census went on to become IBM.

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

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

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

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

These recently uncovered walls are all that's left of Washington, D.C's first defense contractor.

A derelict bit of transportation infrastructure hidden in the woods.