Called by pro mountain bikers the “most extreme 100-miler in the world,” the Rincon de la Vieja Challenge 100-mile mountain bike race at Rincon de la Vieja Volcano in Guanacaste, Costa Rica recently upped its status to become the first international chapter of the National Ultra Endurance Series (NUE).
The NUE is a series of twelve 100-mile mountain bike races across the United States. Winner of the 2014 NUE series, Brenda Simril of Tennessee, also took first place in the Open Category for Women
