This rare triple-jurisdiction drawbridge passes through Virginia, Maryland, and Washington, D.C.

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

An isolated island home to one of the oldest English-speaking communities in the region and Maryland's state dessert.

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

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.

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

This suburban house is made of dirt, and almost sparked a revolution in home construction.

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

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

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

America's first nuclear-powered merchant ship is now a time warp to the atomic age.

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

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

Three abandoned missile silos are hiding in plain sight behind a suburban development in Maryland.

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

Baltimore's classic clock tower was once topped by a rotating, 20-ton medicine bottle.

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

A mammoth pair of Civil War artillery guns abandoned out in the forest.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

The development and impact of electronic media showcased in a picturesque farmhouse in Maryland.

A star fort along the C&O Canal in western Maryland that protected America in three wars.

Two dozen pinball games hidden away inside a most unlikely location.

A benevolent, 16-foot-tall river dragon lives on a suburban lawn.