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Niwot's Challenge

Sedalia, United States • 2-9 May 2026

Niwot's Challenge is a highly demanding ultramarathon held annually in Sedalia, Colorado, along the South Platte River in the Front Range. Modeled after the grueling Barkley Marathons, it features a mostly off-trail course requiring advanced navigation skills using map and compass, with no GPS allowed. The event offers three levels of completion: the Burn Loop (~24 miles, +10,000′ elevation), the Chief's Loop (~50 miles, +20,400′ elevation), and the Deity status (~100 miles, double loops in reverse order). Aid is very limited, and participants must be self-sufficient. The race fosters a close-knit community with secretive course details and a strong emphasis on safety and preparedness. Visit the organization's website for the most recent information.

United States Colorado Sedalia

Race information

Website
100 mi
40800 m+
Deity Status (double Loops)
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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