A unique arch graces the Dolores River Canyon near the Hanging Flume.

The decaying ruins of a failed mining company’s water diversion project cling to the side of a desert canyon.

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

Once a lonely sentinel on the edge of the Great Plains, this rebuilt trading fort offers a glimpse of life on the Santa Fe Trail.

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

A coal fire has been burning underground here since 1896.

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

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

The remains of a World War II-era Japanese American internment camp dot a windswept Colorado hill.

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

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

Neal Cassady may still have an open tab at one of Denver's oldest watering holes.

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

It's easy to forget what century it is as you wander this rustic homestead.

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

This interpretive path lets you get up close and personal with dinosaur bones.

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

This 19th century jail was mainly used to incarcerate the drunk and disorderly.

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

An antique narrow gauge railway line still running through the Colorado and New Mexico mountains.

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

Hidden high on a remote mountain peak is a humbling and mysterious Vietnam War memorial.

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

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