Mountain Biking is a variation of mountain-based sport which is riding using a bicycle off-roads, usually through rough terrain. There are specially designed mountain bikes for this sport. There are variations of mountain biking: cross country, trail riding, all mountain,downhill, free ride, dirt jumping, and trials. Mostly mountain biking is for recreational purposes and trail riding challenges. The riders should equip themselves with gloves, glasses, shoes, hydration systems, GPS navigation devises, pumps, bike tools, and high power lights; for protective gears they should have first aid kits, body armor and pads, and helmets. Mountain biking can be done anywhere, but mostly it is off-road trails. The riders are usually far from the city so they should learn how to repair bikes by themselves. Mountain biking also requires endurance, core strength, balance, bike handling skills, and self reliance from the bikers. The more advanced bikers usually go for steep technical descent, downhilling, dirt jumping, and aerial maneuvers.