The graveyard holding the remains of George Washington's slaves was forgotten for nearly 200 years.

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

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

A museum dedicated exclusively to aircraft used in the military.

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

A home built with marble tombstones from the graves of 2,200 Union soldiers buried in a Virginia cemetery.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

The only recreation of William Shakespeare's indoor playhouse.

A small Richmond island dotted with the remnants of hundreds of years of history.

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

Edgar Allan Poe's old dorm is now a shrine to the author's legacy.

This elaborate towering structure was once famed for its revolutionary height.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

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

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

Elevated freight railway turned wildly successful urban park.

The bank that helped fund the Mexican-American War and the purchase of Alaska met its downfall after helping Augusto Pinochet launder money.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

Corn-inthian columns with a uniquely American take on neoclassical architecture.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

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.