Desert RATS Trail Running Festival by UTMB
Desert RATS Trail Running Festival by UTMB – 50K
Fruita CO, Mack Exit, Hawkeye Trailhead
Race guide
Updated 18 July 2026
The Desert RATS Trail Running Festival by UTMB – 50K is a 48 km desert race from the Hawkeye Trailhead at the Mack Exit near Fruita, Colorado. With 1,007 m of climbing and a high point of 1,638 m, it sits between the festival's short 21K and its demanding 100K — long enough to be a genuine ultra test, yet runnable enough to suit both experienced racers chasing a fast time and those stepping up to the 50 km distance for the first time. The course shares much of its terrain with the longer 100K, taking in Rustler's, Pizza Overlook, Crossroads and the Troybuilt trail before returning to the start. Crew access at the start, both Rustler's stations, Troybuilt and the finish means support is available at several key points, and the modest total climb makes this a course where consistent running, not climbing strength, sets the times.
The Course & Terrain
The 50K holds a narrow altitude band between roughly 1,385 m and 1,638 m throughout — its 1,007 m of climb is spread across constant small rollers rather than concentrated in any big ascent. From the start at 1,429 m the course drops slightly out to Rustler's 1 (9.9 km, 1,385 m) and Rustler's 2 (15.6 km, 1,385 m), both low points on the course and both crew-accessible, making the opening stretch fast and inviting. After Rustler's the ground rises gently to Pizza Overlook (22.2 km, 1,453 m) and Crossroads (28.5 km, 1,440 m), the course's timing checkpoint. The final third runs out to the Troybuilt trail (39 km, 1,410 m), the last crew point, before returning to the finish at 1,429 m. Across the whole 48 km the elevation range is only about 250 m, so the challenge is sustaining pace over rolling, exposed high-desert singletrack rather than surviving any single climb.
Where the Race Is Won or Lost
With no decisive climb, the race is shaped by the long middle and closing sections from Crossroads (28.5 km) through Troybuilt (39 km) to the finish. The early miles to Rustler's are downhill-leaning and easy to run too hard; the true test is holding form once you turn back into the rising desert after Pizza Overlook and Crossroads in the heat of the day. The single intermediate cut-off falls at Crossroads at 12:00 (28.5 km), so reaching that checkpoint with time in hand is the tactical priority — do it comfortably and the run through Troybuilt to the 17:00 finish becomes very achievable. Troybuilt at 39 km is the last chance to refresh with crew before the closing 9 km, so arriving there in good shape, well-hydrated and topped up, is what separates a strong finish from a grind to the line.
How to Pace & Fuel It
The 50K has two timing gates: Crossroads at 12:00 (28.5 km) and the finish at 17:00 (48 km). The generous five-hour window for the final 19.5 km means most runners are limited by the desert conditions rather than the clock, but the early Crossroads cut-off rewards a controlled but purposeful first half. Resist the temptation to hammer the downhill-leaning opening to Rustler's — bank a rhythm you can sustain when the trail tilts back up. Crew access at the start, both Rustler's stations and Troybuilt lets you stage fluids and calories at regular intervals; use Troybuilt (39 km) in particular to set up a strong final push. Aid spacing is comfortable, generally under 15 km between stations, so a standard ultra fueling plan of steady carbohydrate intake plus consistent electrolytes will carry you through — the priority is drinking to the heat rather than waiting until you feel thirsty.
Conditions to Expect
This is exposed Colorado high desert at around 1,385-1,638 m, with strong sun, little shade and a course that unfolds across the hottest part of the day given the 17:00 finish cut-off. Heat management and hydration are the defining challenges — far more than the modest 1,007 m of climb — so plan your fluid carry and electrolyte strategy around desert temperatures rather than the gentle profile. The footing is typical high-desert singletrack, rocky and dusty in stretches, so shoes with dependable grip and some rock protection help on the rollers around Pizza Overlook and Troybuilt. Sun protection is essential: a cap, sunglasses and sunscreen make a real difference over five-plus hours of open trail. Most runners will finish in daylight, but carrying a light and knowing your pace against the Crossroads cut-off keeps a slower day safely on track.
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Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-17) · official source
0 km · 1429 m · —
9.9 km · 1385 m · —
15.6 km · 1385 m · —
22.2 km · 1453 m · —
28.5 km · 1440 m · Sat 12:00
39 km · 1410 m · —
48 km · 1429 m · Sat 17:00
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