Nestled at the top of the Continental Divide marks the starting line of an annual adventure. A punishing mixture of loose sand, technical singletrack, and over 16,000 feet of vertical gain awaits those bold enough to embark on it. One day. Three races. Over 500 competitors. Every July, mountain bikers craving a challenge bathed in both grit and beauty flock to Butte, Montana for what has been deemed “the most difficult mountain bike race" in the United States.