Hardrock 100
Race Day Weather
Cool start, warming finish
Runners will face a cool start at 47°F, rising to 66°F by the finish. A light tailwind will aid performance in various segments, particularly from miles 12-21 and 22-25. Humidity is moderate at 48%, and runners should consider pacing conservatively on the initial climbs. The finish will feel warmer than the start, so hydration and proper gear adjustments will be crucial as temperatures rise during the day.
This course climbs 4,587 ft to its high point and back, so we look at it at 2 points, not just the start line. In a typical year, at 9:00/mi, you start at 47° and finish around 8:59 PM in 60°.
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Race Info
The Hardrock 100 is a grueling ultramarathon that challenges runners with a 102.5-mile loop through Colorado's rugged San Juan Mountains. Traversing 4WD roads, dirt trails, and cross-country terrain, the course features a cumulative elevation change of 66,394 feet, with an average elevation exceeding 11,000 feet. Runners navigate 13 major passes between 12,000 and 13,000 feet, culminating at the 14,048-foot summit of Handies Peak. The race honors the area's mining heritage, requiring participants to "kiss the Hardrock," a ram's head painted on a stone, upon completion. Held annually in early July, the event is renowned for its demanding conditions, including steep climbs, snow packs, river crossings, and boulder fields, making it a premier test of endurance and mountaineering skills.
