An abandoned concrete jungle surrounded by a lush park.

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

A remote sandstone plateau named for a legendary cattle rustler.

This small piece of railroad history sits behind the parking lot of a chain grocery store.

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

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

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

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

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

A coal fire has been burning underground here since 1896.

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

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

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

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

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

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

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.

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

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

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

This razorback ridgeline has doubled as a scenic drive since the early 1900s.

The huge collection of paintings of the American West is one of Denver's best-kept secrets.

A recreation of an Old West apothecary full of curios.

The largest dinosaur trackway in North America is tucked away among this canyon's ghosts and archaeological gems.