Monster of Mazinaw Trail Race

Cloyne, Canada • 20 Sep 2025

The Monster of Mazinaw Trail Race is an ultramarathon event held at Bon Echo Provincial Park in Cloyne, Ontario. It features challenging trail distances of 10k, 30k, and 43k, with the 43k race being Canada's shortest ultramarathon. The course offers a mix of wide groomed trails and technical, rocky single tracks with steep ascents and descents, requiring runners to be experienced and self-reliant, especially on back-country sections up to 17 km without aid stations.

The race is well-marked and includes aid stations with water, electrolyte drinks, and snacks. Participants receive a race tee, bib, and finisher's medal. The event celebrates the natural beauty of the park, including the iconic Mazinaw Rock and local wildlife. Visit the organization's website for the most recent information.

Race information

43 km
43k Trail Race
30 km
575 m+
30k Trail Race
10 km
10k Trail Race (approximately 11k)
Visit the organization's website for the most recent information.
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