Eons ago, a rushing lava river formed this pristine passage through solid rock.

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

A reproduction of earth's many biomes.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

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

A wealth of pop culture statuary and green chile dishes give this roadside restaurant clout.

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

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

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

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."

This small piece of railroad history sits behind the parking lot of a chain grocery store.

While comics are the main attraction at this megastore, the second floor plays host to an exhibit fit for a museum.

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

This iconic science fiction house still looks like something from the future.

The final resting place of American icon Buffalo Bill, and a museum that aids in telling his tale.

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.

The highest bridge in America was built for an almost unnervingly small amount of money.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

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

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

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.