Niwot's Challenge

Sedalia, United States • 10 May 2025

Niwot's Challenge is a challenging ultramarathon held annually in Colorado's Front Range, designed for experienced runners. Modeled after the Barkley Marathons, this grassroots event features a secretive course that requires participants to navigate primarily off-trail using a map and compass. With a limited capacity of 40 runners, the event emphasizes self-sufficiency and decision-making, as aid is minimal. Participants can aim for different achievement levels, including "Chief" and "Deity" status, based on the distance and difficulty of the loops completed. The event fosters a unique community spirit, encouraging camaraderie and adventure among its participants. Visit the organization's website for the most recent information.

Race information

100 mi
40800 m+
Deity Loop
50 mi
20400 m+
Chief's Loop
24 mi
10000 m+
Burn Loop
Visit the organization's website for the most recent information.
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