The Frozen Otter Ultra Trek is by far one of the toughest races in the Midwest and with less than a 10% completion rate, possibly the country. Racers traverse 64 miles of Wisconsin’s hilly terrain left in the wake of the great Wisconsin Glacier. As if the sheer feat of conquering the mileage isn’t enough, racers must do it completely self supported, on trail, in the dead of winter.
Click to reach the official site
Information about the event is available in : English