10 Seconds Flat

Boulder County, Colorado, United States

11.7 miles (18.8 km) · 7,056 ft elevation gain · Loop · trail · Route

10 Seconds Flat is a 11.7-mile loop route in Boulder County, Colorado, United States, gaining 7,078 feet of elevation. The route follows a rolling elevation profile. The terrain breaks into 5 distinct sections including 1 significant climb. The longest climb covers 1.2 miles gaining 1,204 feet at an average 18.9% grade. Only 5% of the terrain is runnable — expect substantial hiking throughout. The route opens with a climb and finishes with a descent.