Desert RATS Trail Running Festival by UTMB

The Desert RATS Trail Running Festival by UTMB runs on the Kokopelli trail system in the Mack Ridge area west of Fruita, in western Colorado, and starts and finishes at the Hawkeye Trailhead off the Mack exit. Its ultra is the 100K, which starts at 5 a.m. on the Saturday and covers 100 km with 2,050 m of climbing on a 20-hour limit: a lap of the Kokopelli loops, then out along the Kokopelli Trail's four-wheel-drive road to the Western Rim loop and back.

The weekend also has a 50K, which measures 48 km, a 21K and a 10K. Entry is first come, first served, and the 100K counts as a Western States 100 qualifier.

The 100K opens with a mile of dirt road before the singletrack of the Kokopelli loops past Rustler's, Pizza Overlook and Crossroads, then heads west past Salt Creek and Rabbit Valley to the Western Rim loop and comes back the same way. Cutoffs fall at Rabbit Valley and the Western Rim in both directions, at Salt Creek on the way back, and at the finish, which closes at 1 a.m. Sunday.

Registration for 2027 is open on the race's site, first come, first served, and closes online on Sunday, April 4, 2027 or when a distance sells out, with no waiting list. The expo takes entries for any distance still open, but there is no race-day registration. Entries are non-refundable and non-transferable, and can be deferred once to the next year until March 11, 2027.