Mountain biking is the sport of riding bicycles off-road, often over rough terrain, using specially designed mountain bikes. Mountain bikes share similarities with other bikes, but incorporate features designed to enhance durability and performance in rough terrain. Mountain biking can generally be broken down into multiple categories: cross country, trail riding, all mountain, downhill, freeride, slopestyle, dirt jumping, and trials. The vast majority of mountain biking falls into the recreational cross country, Trail Riding and Enduro categories. This individual sport requires endurance, core strength and balance, bike handling skills, and self- reliance. Advanced riders pursue steep technical descents. Mountain biking can be performed almost anywhere from a back yard to a gravel road, but the majority of mountain bikers ride off-road trails, whether country back roads, fire roads, or single-track (narrow trails that wind through forests, mountains, deserts, or fields).