The Decoy Capital of the World.

A historic cemetery with unique artwork, a Civil War fort, and also happens to be the site of the Battle of Bladensburg.

This 16-foot, intricately detailed model of the Gearing-class destroyer has been called the most detailed model ship ever built.

The final resting place of an iconic drag performer is decorated with pearls and hot-pink lipstick.

This grove was planted more than a century ago by the War Mothers of World War I.

This advertisement for talcum powder was painted on the rock face and has since defied removal.

The bridge's highly-contested plaque (once again) honors Confederate President Jefferson Davis.

Unannounced visitors are now welcome at the site of the largest Prohibition-era bootlegging operation in the region.

The U.S. government built the million-pound stack of steel during the Space Race.

Proto-CIA agents trained with grenades in the sand traps and fired machine guns from the fairways.

A Maryland museum dedicated to Black history, housed in a historic church.

This golfball sized platinum iridium cylinder is the official starting point for all national weight calibrations

The hidden ruins of a mill that is linked to an attempt to assassinate the vice president of the United States.

Tiny observatory made big contributions to the study of the Earth's motion.

The wooded estate of the Forest Service employee responsible for D.C.’s cherry blossom trees.

The headquarters of the Audubon Naturalist Society is a small slice of heaven for nature lovers.

This massive swimming pool is the high tech home to the human-powered submarine races.

A relic of FDR's brief foray into utopian urban planning.

A swimming hole in the historic industrial quarry that supplied the marble for the Baltimore Washington Monument.

One of the only memorials dedicated to journalists who died in combat.

A small 19th-century graveyard tucked away in the middle of a suburban neighborhood.

Its diverse collection of computers and technology spans the ages.

The United States' oldest Episcopal church still in active use.

Home of the physician who set the leg of John Wilkes Booth after the Lincoln assassination.