In an alcove of this historic library, you can find murals painted in the 1930s by an artist who went on to create some of Disney's most iconic animated films.

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

The local community brought back this land to transform it into a nature preserve.

A haunting tribute to pioneering photographer Clover Adams.

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

A celebrity from the late Cretaceous period.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

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

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

This one-room doctor's office has been moved twice, and now lives on as a museum.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

Surrounded by traditional homes, this Tolkien-esque dwelling stands out on a quiet street in suburban Maryland.

One of the oldest standing structures in Montgomery County, Maryland.

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

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

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

Concerned residents saved this historic house and garden from demolition.

The shelves in the back of this thrift store are devoted to saving, not selling, retro tech.

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

Press 1 for knock-knock jokes.

An old pay phone rewired to play local bird calls and songs at the press of a button.

The final resting place of the tragic king and queen of the Jazz Age is tucked away in a small Maryland graveyard.