Fourmidable

Auburn, United States • 21 Feb 2026

The FOURmidable is a trail running event held in Auburn, California, featuring distances of 50K, 35.5K, half marathon, and 13K. Set in the scenic Sierra Nevada foothills, the race offers a challenging course through rugged and picturesque terrain, providing runners with a true test of endurance amidst natural beauty. The event fosters community support by matching runner donations to create a prize purse for the 50K race, with additional bonuses for breaking course records. This race is ideal for trail enthusiasts seeking a competitive and rewarding outdoor experience in a stunning setting. 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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