These aggressively sustainable art homes look like something out of 1970's science fiction.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

A museum dedicated to the alleged Roswell Incident.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

Devilish landscape, once cinema home to giant alien bugs, now derelict roadside attraction.

An architect's childhood fantasy treehouse made real.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

A hotel with a rich Wild West history of miners and bootleggers.

Each year, teams of the world's best snow sculptors have 65 hours to create frozen masterpieces.

Unlike most arches, this geological oddity formed in a volcanic dike.

Hidden beyond a kitschy giant beetle is this remarkably sprawling collection of preserved insects.

The huge collection of paintings of the American West is one of Denver's best-kept secrets.

Possibly the world's only drive-in movie theater with an attached motel.

One of the largest Buddhist stupas in North America is built of concrete designed to last 1,000 years.

A collection of fading fantasy tchotchkes lines this dirt road in the Colorado wilderness.

The scene of one of the darkest moments in American labor history has been left essentially untouched since the tragedy.

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

The highest paved road in North America winds its way up Mount Blue Sky in Colorado to an altitude of 14,130 feet above sea level.

This spectacular track has run continuously since 1882.

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

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

When ecosystems collide in the arid Southwest.