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

This quirky hot springs town known to locals as "T or C" was named after a radio show.

This is one really big nut.

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

This public square capitalized on a single Eagles reference to bring some life back to an Arizona town.

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

A motel dedicated to Southwestern nostalgia.

Petroglyphs, bird watching, and a 100-year-old Ranch in one location.

This site honors the end of a 100-year boundary dispute between the United States and Mexico—all started by a river's shifting course.

A giant "X" symbolizes the blood spilled from the brutal Juárez drug wars.

El Paso's only historic house museum is an adobe mansion built by a prominent multicultural borderlands family.

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.

The story of Two Guns, Arizona could easily be described as a Shakespearian tragedy on Route 66.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

This sinkhole in the Arizona desert is filled with carbonated, arsenic-rich water

This rusted car found in Petrified Forest National Park's Route 66 exhibit may be the most photographed abandoned car in the country.

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

This site is home to ancient petroglyphs and pictographs dating back to 6,000 B.C.

This Moab institution functions as both a rock store and a small natural history museum.

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

A crack flared at the base provides a pathway completely through a sandstone ridge near Moab.

It's safe—and permitted—to walk across these twin natural sandstone arches.

Few things look more out of place than the electric blue ponds in the reddish-brown desert of Utah.

This raised bulls-eye visible from space was the subject of an intense geologic controversy.