Marin County's most famous trails - Coastal, Miwok, Steep Ravine and the Dipsea - provide the spectacular setting for this classic, single-loop race. Founded in 1998, this event is under new race directorship and has the full backing of Marin's largest running club. Only minutes from downtown San Francisco, the Tamalpa Headlands 50K is a demanding ultra marathon with over 7,300 feet of elevation change.