This rock in the middle of a river in Jayuya contains dozens of Pre-Columbian Taíno petroglyphs.

Located in the world's highest-altitude Dark Sky Community, this observatory welcomes amateur and professional astronomers alike.

This remote Colorado canyon is home to the second-largest collection of natural arches in the world.

It takes a nine-mile hike to reach these hot springs, but weary hikers are rewarded with stunning views and a warm soak.

Two tall rocks sit at the center of this site, once the home of a large Ancestral Puebloan community.

Historic, 19th-century wagon wheel ruts cut into soft volcanic ash.

This massive home was constructed by one of the greatest conservationists in Colorado history.

16,500-acre ranch filled with American heritage, geological wonders, and a giant pile of tires is the crown jewel of an intriguing tug-of-war.

A seven-story 1920s mausoleum outside Denver houses thousands of remains.

A prehistoric rock shelter that's literally in someone's backyard.

The remains of an early 1900s dude ranch that operated until the 1970s.

The site where a nuclear bomb was lowered over 8,000 feet underground and detonated as an experiment in natural gas extraction.

A coal fire has been burning underground here since 1896.

The site of the "Bone Wars" between two rival paleontologists during the dinosaur rush of the 19th century.

At one time this small mining village was the highest town in America but now it sits abandoned while the mine churns on.

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

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

Climb to the top of this spiritual tower, and you'll be rewarded with spectacular views.

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

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

The wreckage of a World War II bomber is hidden high in the Colorado wilderness.

This once-popular otherworldly landscape was formed by one of the largest volcanic eruptions in history.

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.

Colorado's only true geyser is hidden within the San Juan National Forest.