This ruined fort hidden at the top of Central Park can't seem to keep from losing its historical plaques.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

The "Seinfeld" diner.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

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

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

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.

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

The romance of early commercial flight still fills this Art Deco destination.

The remains of a historic plantation nestled in between a parking lot and the rental car return at Reagan National Airport.

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

Long buried under the 20th-century landscape, this lift lock of the Alexandria Canal is the lone remnant of an ambitious early American transportation project.

The final resting place of an unidentified revolutionary soldier sits behind a Virginia church.

This stately building in Alexandria, Virginia was built by Freemasons to honor one of their most famous members.

This 29-ton granite ball spins around at the slightest touch thanks to a scientific phenomenon.

This train station inspired the name of a 1970's rock band and provided the backdrop for their album cover.

A gift from Japan, 17th-century lantern stands among the cherry trees at D.C.'s Tidal Basin.

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

The "lovely red Vega" of the legendary record-settling pilot.

Government testing at the asylum briefly explored using marijuana as a "truth serum" on Nazi prisoners of war.

The national park was once a plantation estate.

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