First Flatiron (Boulder, CO)

Boulder County, Colorado, United States

2.4 miles (3.9 km) · 1,544 ft elevation gain · Loop · trail · Route

The First Flatiron (Boulder, CO) route traverses 2.4 miles through Boulder County, Colorado, United States. Elevation gain totals 1,544 feet, with 1,538 feet of descent. The most significant ascent covers 1.2 miles and gains 1,510 feet. Vertical rate measures 634 feet of gain per mile. About 7% of the distance is runnable terrain. Terrain is predominantly trail. Technical difficulty: mountainous. This route ranks at the 99.74th percentile for difficulty among similar distances. The route draws trail runners and hikers interested in technical terrain in Colorado.