Tamalpa Headlands 50K

Mill Valley, United States • 15 Aug 2026

Tamalpa Headlands 50K - August 15, 2026

The Tamalpa Headlands 50K is a single loop ultramarathon held in the Marin Headlands near Sausalito, California, with the start and finish at Santos Meadows just south of Muir Woods. The event lists two distance options.

  • 50K
  • Kids' One Mile Challenge

Founded in 1998, the course covers approximately 6,500 feet of elevation gain and uses many local trails, including Coastal, Miwok, Steep Ravine, Matt Davis and Dipsea. Terrain includes fire road sections, steep climbs, flowy singletrack and technical stretches, with views of the Bay Area and the Pacific Ocean. The finish and after party take place at Santos Meadows.

Aid stations are located at Rodeo Beach (mile 8.3), Tennessee Valley East (mile 11.5), Highway 1 (mile 14.8), Cardiac first pass (mile 19.5), Stinson Beach (mile 24.1), Cardiac second pass (mile 27.7), and the Santos Meadows finish area. The event uses time limits and cutoffs at several course points; these are posted by the organizers.

Event rules include a cup free policy requiring runners to carry a collapsible cup or personal drinking device, visible race numbers worn on the front, and disqualification for cutting switchbacks. Dogs are not allowed at Santos Meadows. If a runner withdraws they should notify a race official or aid station captain.

Refund policy: 50% refund available for withdrawals by 06/30. No refunds, rollovers, or exchanges after that date. Registration closes August 11 at 11:59 PM PT. 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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