D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

The first memorial dedicated solely to the Black troops who fought for the Union.

A bit of retro transportation flair preserved in the world's largest department store.

A terrific purveyor of natural history objects and curios.

Elevated freight railway turned wildly successful urban park.

One of only two commuter aerial tramways in the United States.

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

Built in 1945, this historic train station has a new lease on life with its baggage area serving as an event space.

A lawn full of retired spacecraft on display at one of NASA's first research labs.

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

This dig site outside D.C. is known for its exceptionally high density of baby dinosaur fossils and dinosaur eggs.

A local farm's collection of unusual structures from a now defunct storybook amusement park.

This bug-eyed water wheel uses the power of the Sun to clean up Baltimore Harbor.

The childhood home of the Sultan of Swat is just a line drive away from Oriole Park at Camden Yards.

The first American department store, and home to the largest operating musical instrument in the world.

A toxic ghost town sitting atop a massive coal fire.

Try not to get slimed in Tribeca.

The oldest farmer's market in America is so ancient it was approved by the King of England.

A modern ghost town whose inhabitants were driven away by the growth of nuclear power.

A failed piece of Orientalism has become the proud symbol of a community.

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

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

A girls' boarding school inspired by the Chicago World's Fair, once abandoned, now restored to strange and scenic glory.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.