They sort through millions of dollars worth of diplomatic gifts on behalf of the government.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

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

The word "Watergate" will forever be associated with the infamous scandal in 1972, but this fountain is famous in its own right.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

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

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

The oldest house in Washington, D.C. wasn't originally constructed in the nation's capital.

Before Nixon, "watergate" meant canals.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.

Born a slave on the Arlington estate, Parks dug the first graves at Arlington National Cemetery, and was buried there, too.

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

This one-room doctor's office has been moved twice, and now lives on as a museum.

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

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

An oft-overlooked, magically musical monolith that stands majestically between Arlington Cemetery and the Iwo Jima Memorial.

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.

Recorded as the first person buried in Arlington Cemetery.

Though his role as the inventor of baseball may be up for debate, fans still festoon Doubleday's grave with baseballs.

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

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