A coal fire has been burning underground here since 1896.

The site of a defunct mill, that once supplied marble for the construction of the Lincoln Memorial.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

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

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

Silver in the hills led to the speedy creation of this boom town and a lack of it saw the town abandoned nearly as quickly.

All that remains of this once-booming mining town are the ruins of a saloon.

A futuristic hovertrain is parked unceremoniously alongside a nondescript road.

A mental health hospital dating back more than 139 years, now features a museum.

Abandoned silver mine strewn with wrecked and twisted structures.

An ADA-accessible trail and deck offering stunning views of Colorado’s Mount of the Holy Cross.

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

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

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

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

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

Inspired by a music box, a small town Vietnam vet carved an entire carousel full of animals by hand.

A museum dedicated to the mysterious cryptid.

When this 160-year-old church was being built, a stonemason included a hidden homage to his late daughter.

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

This now-abandoned outcrop is an important Native American spiritual site, overtaken by European settlers and mining pollution.

According to local legend, a tree grew from the stake that killed this alleged vampire. In reality, he probably died from influenza.

Over 1.3 million confiscated wildlife products fill this macabre menagerie of illegal animal specimens.

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