The haunted reputation of these abandoned Colorado train tunnels is probably not helped by the terrifying spiked fence.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

This super steep hike ascends 2,000 feet in less than a mile.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

The largest source of fossilized insects anywhere.

Abandoned silver mine strewn with wrecked and twisted structures.

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

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

Isak Heartstone, a 15-foot wooden troll made out of recycled materials.

Above Breckenridge, a destructive mining technique sits sunken in a small pond.

A collection of fading fantasy tchotchkes lines this dirt road in the Colorado wilderness.

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.

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

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

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

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.

Paleoamericans built these ancient walls high in the Colorado Rockies as part of an extensive hunting system.

These decaying bridges 1,000 feet high are a reminder of the skill it took to cross the Colorado Rockies by rail.

The world's largest carnivore sanctuary is home to over 450 meat-eating rescues.

This deserted Gold Rush town is home to a Masonic lodge that, strangely enough, still holds meetings.

The burial grounds of a secret society includes fences topped with fake Tesla balls.

Final resting place of a 19th century gold prospector and convicted cannibal.

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