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 Ontario, Canada. Featuring distances of 10k, 30k, and Canada's shortest ultramarathon at 43k, the race offers a challenging course with a mix of wide groomed trails and technical, rocky single tracks. Participants navigate rugged back-country trails with steep ascents and descents, requiring self-reliance over long aid-free sections.

The race is well-marked and sanctioned by Athletics Ontario. Runners enjoy stunning natural scenery, including views of Mazinaw Rock, a National Historic Site known for its pictographs. The event emphasizes trail experience, wildlife awareness, and a supportive atmosphere with aid stations providing hydration and snacks. 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.
Trail runs nearby

The Last Hour is an 8km trail run held at Vanderwater Conservation Area in Thomasburg, Ontario, as the final race in the Friday Night Happy Hour Series. The course features gently rolling terrain through beautiful pine groves, old boulder fields, and alongside the Moira River, with wide trails ideal..