The Big Alta

Lucas Valley-Marinwood, United States • 20-22 Mar 2026

The Big Alta - Marin County trail running weekend, March 20-22, 2026

The Big Alta is a trail running event held in Marinwood, California, centered at the Marinwood Community Center. The event is jointly organized by Freetrail and Daybreak Racing and takes place on trails in Marin County that are used by Freetrail.

Courses include single-loop and point-to-point formats across the county's higher terrain. The routes summit many of the highest points in Marin County and provide extended vistas across the San Francisco Bay Area. The event program mentions live coverage and a finish line experience as part of the race weekend.

Distances offered:

  • 50K single loop
  • 100K point-to-point
  • 28K single loop

Registration for the event closes on Sun, Mar 15. The description focuses on course types, organizers, location, and the scenic nature of the routes within Marin County and the Bay Area. Visit the organization's website for the most recent information.

Race information

100 km
100k
50 km
50k
28 km
28k
Visit the organization's website for the most recent information.
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