Welcome to the most difficult mountain bike race in the country: The Butte 100. The Butte 100 race weekend consists of three individual races, a 100 mile, 50 mile and the Sorini 25, taking place atop the Continental Divide just outside of Butte, Montana. The race has grown from a small group of dedicated locals on a gravel road, to world-class athletes competing on world-class trails. With outstanding partnerships with the USFS, BLM, community of Butte, our generous sponsors, and the “neon army” of volunteers, the Butte 100 races continue to provide the best mountain bike racing experience possible. Thanks for visiting.