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The Big Alta

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

Event Information

The Big Alta is a trail running event in Marin County, California, organized by Freetrail and Daybreak Racing.

The event offers three race distances:

  • 100K, a point-to-point course
  • 50K, a single-loop course
  • 28K, a single-loop course

All three courses are designed to be scenic and summit many of the highest points in Marin County, providing views of the San Francisco Bay Area. The event includes support and a finish line celebration.

Location

The race starts at the Marinwood Community Center in Marinwood, California.

Schedule

The event takes place from March 20 to March 22, 2026. The 50K starts on Friday, the 100K on Saturday, and the 28K on Sunday. Visit the organization's website for the most recent information.

United States California Lucas Valley-Marinwood

Race information

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