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

This popular pitstop lives up to its name.

Twenty-seven massive radio antennas on the high plains of New Mexico search for life on other planets.

Legends surround this jagged rock formation in the New Mexico desert.

A museum dedicated to the alleged Roswell Incident.

The location where the iconic movie character declared it was time to go home.

Erosion and various mineral deposits give this striking canyon its distinct color and soft appearance.

The fifth-longest natural arch in the world, and the longest outside China.

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

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

The arch that celebrated the completion of the Lincoln and Victory highways.

The farthest you can be in the contiguous U.S. from a McDonald's location.

Thousands of turbines whir at at the origin of North American wind power.

Nuclear waste dump site now an environmental sanctuary.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

A public fountain that spouts "health water" from a nearby spring.

A Roman-style column in Oregon hides a spiral staircase inside.

Only known mainland rookery of the threatened Stellar sea lion.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

The longest and widest floating bridge in the world.

A rare tour of a commercial jet assembly plant, held inside one of the largest buildings in the world.

Allowing humans and fish alike to migrate from freshwater to saltwater and back again.

This large Sitka spruce that appears to be floating in mid-air, has defied logic for years.