When ecosystems collide in the arid Southwest.

A short but powerful waterfall resides amid Colorado’s Great Sand Dunes.

This National Natural Landmark is one of the best examples of a “mass wasting” in the world.

A glimpse of a waterfall is reached by a steel catwalk along a slot canyon located in an Ouray city park.

An antique narrow gauge railway line still running through the Colorado and New Mexico mountains.

A river runs through this remote valley in a very unexpected way.

This hot dog-shaped diner has moved all around Colorado, never been to New York.

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

An impressive collection of over 50,000 minerals including moon rock from the Apollo 17 mission.

Community owned and operated, this property is home to a diverse set of nudists.

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

For one month, the fields and skies of Gibbon, Nebraska, come alive with one of the largest gatherings of sandhill cranes in North America.

Visitors to this museum will uncover a whimsical collection of marbles from across time.

Underneath downtown Lincoln resides a network of caves that was also the city's first brewery.

A brick-paved former section of the historic coast-to-coast highway.

Other-worldly rock formations and ancient fossils abound in this unique stretch of Nebraska badlands.

This erect, phallic geological spire wasn't always named so domestically.

This small shop walked so America could run on Dunkin'.

Narrow slot canyons in a badland eroded into soft sedimentary rock provide an otherworldly landscape in this remote Nevada state park.

An unusual slot canyon in the Aztec/Navajo Sandstone has a cross-section like an inverted old-fashioned keyhole.

Harder layers in colorful sandstone weather out as prominent “fins" and even more intricate and bizarre shapes.

Located in the remote Monitor Valley, this travertine bowl contains a scalding pool of water.

Once a sewer culvert, this road tunnel now offers cyclists and pedestrians a subterranean stroll under the C&O Canal.

An abandoned railroad tunnel transformed into a creepy path for hikers and cyclists.