A monument at the site of the Towner School Bus Tragedy, which lead to changes in school bus safety.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

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

The largest self-built castle in the U.S., six decades in the making.

A coal fire has been burning underground here since 1896.

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

This nearly abandoned town was once a thriving mining community until a series of fires.

This historic stone barn is the former home of legendary cattleman Charles “Lonesome Dove” Goodnight.

This three-mile concrete levee in Pueblo, Colorado was transformed into the world’s longest painting.

This naturally-sourced hot spring is now home to a clothing-optional resort.

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

This Great Plains museum pays tribute to both the prosperity and tragedy of the North American fur trade.

This fully restored synagogue explores the American Jewish experience along the old frontier.

Victorian "Fancy Craft" Hair Wreaths and Relics.

Inside this shop, visitors are treated to a unique blend of natural history and art.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

The home of a formerly enslaved man who went on to become a prospector, entrepreneur, and activist for Black rights.

In the middle of a suburban Denver neighborhood is a cave that once provided solace for a prominent Ute chief and his family.

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

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

Toss a Frisbee through the ruins of this Colorado gold mining town.

A Rocky Mountain city provides a happy ending for a pinto pony and his Brobdingnagian red chair.

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

This sidewalk tribute honors Colorado's great culinary creation.