The Slab (Flatirons, Boulder, CO)

Boulder County, Colorado, United States

3.2 miles (5.1 km) · 1,280 ft elevation gain · Loop · trail · Route

The Slab (Flatirons, Boulder, CO) covers 3.2 miles across Boulder County, Colorado, United States. Runners face 1,280 feet of climbing with 1,306 feet of loss. The longest climb spans 1.5 miles with 1,308 feet of gain. Elevation gain averages 401 feet per mile. The course is 15% runnable, with the remainder requiring hiking on steep or technical sections. Trail comprises the majority of the course. The course features mountainous terrain. The course difficulty of 40.2 puts it in the top 2.049999999999997% of challenging routes at this distance. Popular among trail runners and hikers seeking Colorado adventures.