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

D.C. once had its own tiny rival to the New York Stock Exchange.

A line of blue paint marks the route of the inaugural parade.

This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

Was there a small "backpack nuke" hidden in the attic? JFK apparently thought so.

The sculptor was instructed to add “stallion attributes” to the general's bronze mare.

Avoid gangster interaction while window-shopping.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

The sweetest graveyard in the world is filled with headstones for dearly de-pinted ice cream flavors.

One of many gator theme parks, abandoned in the sugar fields of South Florida.

The romance of early commercial flight still fills this Art Deco destination.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

The 72-foot giant escaped confinement in a large patch of mulch only to be reburied in the sandy shores of the Potomac River.

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

A former major munitions plant that has been converted into a sprawling art space.

An original apothecary from 1792.

The narrowest house in America is seven feet of pure spite.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.

A toxic ghost town sitting atop a massive coal fire.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

The highway's southernmost spot is a beloved local attraction.

The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.