Washington's top-secret Cold War-era doomsday communications tower is located in a small neighborhood park.

There just so happens to be a court even higher than the U.S Supreme Court: a basketball court in the building itself.

Home to a vast and influential collection of Shakespeareana.

Helen Keller once broke ground on this historic center for the study of technologies to benefit the hearing impaired.

A diminutive plaque recalls the treetop sniper who almost killed Abe Lincoln.

This forgotten boat elevator was an engineering marvel in its heyday.

Daily lunch spot for many of Washington, D.C.'s cab drivers.

There’s a special club house at the top for the bell ringers.

A fantastic array of trays and cables once whisked books over to the Capitol at 600 feet per minute.

The span is crooked and made from two older recycled bridges.

The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

An overlooked oasis of quiet on the grounds of Washington's monumental basilica.

A clone of a cloned tree that was so important it allegedly had its own guards.

In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

A brass plaque dedicated to a convicted cannibal hangs in the National Press Club, and that's not even the craziest part of the story.

A historic ruin just 20 feet away from a busy highway onramp.

This poor little statue is the most vandalized memorial in Washington.

A hoard of sky catalogs, astrophysical journals, even the works of Galileo and Copernicus.

Where the U.S. government kept its actual treasure, before Fort Knox.

This sandwich shop has a century-old elevator behind a sheet of plexiglass.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

Once the supplier for noteworthy projects like the National Cathedral, this old brickworks now lies abandoned.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.

Light bulbs, scrap wood, and tinfoil comprise this homemade throne of the gods.