This simple stone memorial remembers a secret, Geneva Convention-defying interrogation base from WWII.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.

The rogue roots are gradually consuming some of the historic marble grave markers.

A double agent hid information for the Soviet Union beneath this bridge for more than 20 years.

One street divides a single town that stands in two U.S. states.

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

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

At 207 feet, one of the world's longest continuous escalators.

Where NASA's satellites and rovers phone home.

A burnt-out motel with priceless Native American artwork in the basement, redeveloped into apartments.

This southwest-styled home in Santa Fe claims to be the oldest house in America thanks to an ancient bit of foundation.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

A motel dedicated to Southwestern nostalgia.

This abandoned bootleg attraction was built to cash in on the popularity of classic TV show, F Troop.

This Route 66 classic sports a giant fiberglass rabbit that you can ride.

See massive fossils that are over 200 million years old in northeastern Arizona.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A huge musical instrument played by the ocean.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

An offbeat angle on the ocean viewed through an antiquated lens.