Course
Singletrack trail racing on the shores of Lake Sonoma, starting and finishing at the Lake Sonoma Visitor Center. The 100K follows the original 50 mile out-and-back over Pritchett Peak and through madrone groves; the 50K crosses the landmark Lake Sonoma bridge. The women-only Trail Sisters Half runs point-to-point from Lone Rock. Professionally run aid stations throughout.
Key dates
- ·RegistrationNot open yet
- ★Race daySat 10 Apr 2027
About
Lake Sonoma 100K is a trail ultramarathon through the steep, oak-studded hills above Lake Sonoma in California wine country. The course is known for relentless climbing and technical singletrack, part of the well-established Lake Sonoma ultra race series held each spring near Geyserville.
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