A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

A collection of artifacts from Maryland's maritime past.

Remnants of a storybook amusement park hidden behind a strip mall.

This abandoned Victorian-style house was built in 1884.

A tribute to the beloved, kind-hearted "homeless mayor" of Silver Spring.

FDR's Art Deco hospital tower was hopelessly inefficient.

She stares out across six lanes of traffic, clutching a musket and infant with determination.

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

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

A suburban museum tells the story of a historic transportation network and even provides rides in antique trolley cars.

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

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

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

This 1830s store is believed to be the site of Harriet Tubman's first stand.

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

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

This ruined quarry once produced the distinctive red sandstone used for construction projects in Washington, D.C.

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

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

The rooster who crossed the road lives on forever in Takoma Park, Maryland.

The world's oldest continuously operating airport was founded by the Wright Brothers.

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

Maryland's first (and last standing) toll house on America's first federal road established the state as the "Gateway to the West."

Dogs, cats, horses, monkeys, frogs, and fish are laid to rest at the second-oldest pet cemetery in the U.S.