A plaque commemorates the spot in the Oregon woods where the first-ever Geocache was hidden.

The magic's in the hole!

Portlandia is the second-largest copper repoussé statue in the United States.

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

This stately building in Alexandria, Virginia was built by Freemasons to honor one of their most famous members.

The only tennis court that falls under the jurisdiction of the central bank.

America's first federal monument.

This grave marks the passing of a historic Jane Doe whose identity remains a mystery to this day.

The final resting place of an unidentified revolutionary soldier sits behind a Virginia church.

A massive, majestic mammal watches over pedestrians from his perch atop a former B.P.O.E. lodge.

This small pedestal marks the spot of the first lot of land sold in Alexandria, Virginia in 1749.

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

An original apothecary from 1792.

Home to a 27 room house, this estate was crafted by Black entrepreneur Olander Banks Sr.

This amazingly preserved Gold Rush town is a historian's dream.

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

A small and somewhat hidden memorial to 68 local veterans of the Vietnam War.

Fans of the spicy bright-red sauce can tour where it's made.

A secret rendezvous spot where John S. Mosby and his Rangers would meet to divvy up their loot after raids.

Take shelter from Hawai'i's tropical heat under the massive canopy of largest Banyan tree on the island.

Before Nixon, "watergate" meant canals.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

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

An overlooked tribute to one of the most important peace deals in American history.