Tamalpa Headlands 50K

Mill Valley, United States • 16 Aug 2025

The Tamalpa Headlands 50K is a challenging ultramarathon held annually in Marin County, California, starting and finishing at Santos Meadow near Muir Woods. Covering 50 kilometers with about 6,500 feet of elevation gain, the single-loop course features renowned trails such as Coastal, Miwok, Steep Ravine, Matt Davis, and Dipsea. Runners experience a mix of fast fire roads, steep climbs, technical singletrack, and stunning views of the Bay Area and Pacific Ocean. The event, supported by the Tamalpa Runners and Arc'teryx, also serves as the USATF Trail 50K Championship. Aid stations are strategically placed, and the race emphasizes environmental respect and a cup-free policy. Visit the organization's website for the most recent information.

Race information

50 km
50k
Kids' One Mile Challenge
Visit the organization's website for the most recent information.
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