An overlooked memorial honoring the local Washington residents who died in World War I.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

There’s a hidden military meme engraved on the World War II Memorial.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

The most decorated dog of World War I is preserved in the Smithsonian.

This taxidermy horse was a Civil War hero.

Perhaps the most scandalous statue of America's first president.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

A diminutive memorial marks the site of a successful assassination by a right-wing death squad in America's capital.

A bas relief commemorates the "Nuns of the Battlefield" who cared for soldiers on both sides of the conflict.

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

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.

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

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

This unacceptably tall building was the real reason for Washington, D.C.'s skyscraper ban.

This church built atop a gas station promises to "equip you for the next stage in your life’s journey."

Parking garage where Bob Woodward met Watergate source "Deep Throat."

The national park was once a plantation estate.

This unique historical monument features large concrete spheres designed to resemble fallen stars.

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