A lone historical marker off the highway and scattered debris are all that remain of this Cold War-era missile site.

This museum sits on the site of a decommissioned military communications base.

This pre-Revolutionary War grist mill ground corn and flour for soldiers in seven American wars.

An enormous warehouse filled with parade floats collected from over 50 years of patriotic celebrations.

This abandoned asylum was once a state of the art facility before devolving into one of the most deadly mental institutions in American history.

A priceless collection of the Nation's cryptologic history.

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

Fascinating museum dedicated to the under-appreciated medical history of urology features some wince-inducing devices.

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

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

Bar full of oddities, specimens, artifacts and homages to the great dime museums of the past.

The oldest house in Washington, D.C. wasn't originally constructed in the nation's capital.

This fertility idol of questionable authenticity inspired an iconic Indiana Jones artifact.

Atop this media building, two hives containing more than 30,000 bees keep the surrounding area vibrant.

A public art jibe at one of the United States’ oldest and longest-serving senators.

This statue of the "father of television" stands prominently in the United States Capitol.

Amid the sprawling Defense Intelligence Agency Headquarters is one of Washington's least accessible museums.

A replica of the famous memorial statue at the Normandy American Cemetery hides in an office building in downtown D.C.

The only tennis court that falls under the jurisdiction of the central bank.

A surprising, but overlooked example of geology in the middle of the nation’s capital.

A memorial to a shareholder activist feared by CEOs around the United States.

This unassuming passageway played a key role in one of the most important events in U.S. history.

The district's only illusionarium supports free writing programs for local students with every purchase.

Also known as the Founding Church of Scientology.