A dam that moonlights as a gigantic, brutalist waterslide.

Colorado's only true geyser is hidden within the San Juan National Forest.

A boulder so big and tough, they had to turn it into a landmark.

Once owned by the largest employer in Colorado, these ovens have been abandoned for over a century.

A city park that sits on top of a freeway.

The now-serene site of the largest earthquake ever recorded in North America.

A synth musician's paradise at the heart of a community responsible for the soundtrack to 'Stranger Things.'

An entire subdivision was accidentally built on a flood plain, resulting in its eventual demolition—but the streets are still there.

Austin’s local mountain isn’t really a mountain at all.

A tiny graveyard with a mysterious past.

A volcanic cone that formed over 600 years ago.

A relic of the region's once booming timber industry.

A natural dome made of volcanic glass in Inyo National Forest.

Instead of becoming a power plant, this abandoned complex became a massive letdown.

Abandoned silver mine strewn with wrecked and twisted structures.

An immense cave that has served as an outlaw's treasure trove, an underground dance hall, a nuclear fallout shelter, and much more.

A Google software engineer's Easter egg led to what may be the world's most unusual saved screenshot.

A crash site in the heart of polar bear territory has become a beloved local landmark.

The site of one of history's most indelible and horrific tragedies.

This extraordinary Depression-era expenditure was modeled after a postcard of a Mediterranean hotel.

These mid-century motels once housed the workers who built the Glen Canyon Dam.

Archaeologists believe this panel of petroglyphs depicting descending sheep and other figures in Glen Canyon are 3,000 to 6,000 years old.

This unique art installation used boiler tubes from a decommissioned power plant to resemble Antelope Canyon.

A sculpture for the sun and stars, created by Nancy Holt.