A brass and marble scale model of the solar system embedded in the concrete.

This apartment building designed by a notable Washington D.C. architect housed the Qing Dynasty's Legation.

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

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

A diminutive memorial marks the site of a successful assassination by a right-wing death squad in America's capital.

A public art jibe at one of the United States’ oldest and longest-serving senators.

This site is believed to be connected to the oldest house in Arlington County.

At 207 feet, one of the world's longest continuous escalators.

Parking garage where Bob Woodward met Watergate source "Deep Throat."

This church built atop a gas station promises to "equip you for the next stage in your life’s journey."

This unique historical monument features large concrete spheres designed to resemble fallen stars.

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

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

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.

A gift from Scotland to the United States in memory of the 270 lives lost when Pan Am Flight 103 exploded over Lockerbie due to a terrorist bombing.

The rogue roots are gradually consuming some of the historic marble grave markers.

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

In what is rumored to be an intentional act of spite, this memorial almost completely obscures the nearby grave of a senior officer.

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

An extensive, if one-sided, history of U.S. law enforcement's war on drugs.

The Pentagon is so large that it was planned like a city, complete with internal highway infrastructure.

Rumor has it the hot dog stand was targeted by two Russian nuclear missiles.

Please don’t anchor your boat onto the Department of Defense’s underwater data cables.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.