Founded by John Marino in 1983 and known as "The Toughest 48 hours in Sport," it is the world's premier ultramarathon bicycle race. This 508-mile bicycle race is revered the world over for its epic mountain climbs, stark desert scenery, desolate roads, and its reputation as one of the toughest but most gratifying endurance challenges available, bar none. The course has a total elevation gain of over 35,000', crosses ten mountain passes, and stretches from Santa Clarita (just north of Los Angeles), across the Mojave Desert, through Death Valley, to Twenty Nine Palms.