Fourmidable

Auburn, United States • 21 Feb 2026

FOURmidable is an exciting trail running event set in the stunning Sierra Nevada foothills of Auburn, California. Participants can choose from various race distances, including 50K, 35.5K, half marathon, and 13K, all designed to challenge endurance while showcasing the area's natural beauty. The event emphasizes community support, with prize money funded through donations from runners, which will be matched by Singletrack Running. Additionally, a special award of $500 is offered to any runner who breaks the current course record in the 50K category. This event promises an unforgettable experience for all participants. Visit the organization's website for the most recent information.

Race information

50 km
50k
35 km
35.5k
13 mi
1/2 Marathon
13 km
13k
Visit the organization's website for the most recent information.
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