These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

A little-known hot spring haven right below the highway.

Abandoned silver mine strewn with wrecked and twisted structures.

An architect in Aspen used psychedelics as his muse while building this mushroom masterpiece.

Despite being one of the most photographed vistas in the Rockies these twin peaks are rightfully known as the "Deadly Bells."

This spectacular track has run continuously since 1882.

When ecosystems collide in the arid Southwest.

The superstar of Cold War nuclear bunkers has been featured in countless films but is now barely operational.

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

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

The only retired U.S. nuclear missile silo that is open to the public.

Creek water that starts here has a 50/50 chance of ending up in the Atlantic or the Pacific.

A popular rock that acted as a waymarker for American pioneers.

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

The first declared National Monument in the United States.

Colorful sand dunes create a unique attraction in this part of Utah's red-rock country.

Dozens of rockets and missiles are on display outside a testing facility in the Utah desert.

A unique collection of drawings that represent Fremont Native American culture.

The last SR-71 ever constructed.