Hardrock 100
Race Day Weather
Cool start — fast day potential, big temp swing
A cool 47°F at the start line is ideal for fast times — expect to warm up quickly once you're moving. Temperatures rising to 60°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing.
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.