The Flatirons are striking sandstone formations that grace the eastern slope of Green Mountain outside of Boulder on the Colorado Front Range. These iconic rock formations are a major landmark for the city and provide ample opportunities for outdoor recreation. Their distinctive appearance is the result of millions of years of geological history, making them a fascinating destination for nature enthusiasts.
Hiking The Colorado Flatirons
According to the City of Boulder, the Flatirons are part of the Fountain Formation, a rock unit deposited around 280 million years ago. Around 65 million years ago, tectonic forces caused the formation of the Rocky Mountains, which in turn caused the rocks of the Fountain Formation to rise up and tilt, creating the Flatirons as they appear today. This rich geological history adds to the allure of the area, making it a must-visit for both locals and tourists.
Hiking is one of the best ways to experience the beauty of the Flatirons. The Chautauqua Trailhead off Baseline Road serves as a starting point for many popular trails in the area. Before you begin your hike, stop by the Ranger Cottage for restrooms, maps, brochures, hiking suggestions, and updates on weather, trail conditions, and wildlife closures. The Flatiron Loop Trail is an accessible two-mile hike that winds through the forest beneath the formations. For a touch of history, consider the trail to Woods Quarry, where you can explore the remnants of a sandstone quarry that supplied building materials for Boulder in the late 19th century.