This old train trestle and collapsed tunnel once allowed the railroad to negotiate the steep slopes of the Colorado Rockies.

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

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

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.

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

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

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

Two creeks flow out of either end of this canyon in opposite directions.

This was once the home of Gahan's Saloon, Denver's most storied speakeasy.

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

Possibly the world's only drive-in movie theater with an attached motel.

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

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

A museum dedicated to the mysterious cryptid.

The remains of the dam that unleashed a 15-foot wall of water on Denver.

A research lab and hands-on museum where visitors can experiment with retro technology.

In the early 1900s, hundreds of Black Americans found opportunity in this now-abandoned rural community.

“You better take care of me Lord, if you don't you're gonna have me on your hands.” ― Hunter S. Thompson, Fear and Loathing in Las Vegas.

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

Small teepee-like houses built for TB patients have become sheds, studios, and bus stops around Colorado Springs.

An annual festival celebrating Colorado's most famous frozen corpse.

One of the largest Buddhist stupas in North America is built of concrete designed to last 1,000 years.

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