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San Diego 100

Julian, United States • 8-9 May 2026

The San Diego 100 is a challenging 100-mile ultramarathon held in the mountainous east county of San Diego, California, starting and finishing at Lake Cuyamaca Recreation Area near Julian. The course is a 90% single-track loop featuring rugged terrain with approximately 15,400 feet of elevation gain and loss, traversing sections of the Pacific Crest Trail, Noble Canyon, Cuyamaca and Anza Borrego State Parks, and Mt. Laguna. Known for its hot, dry conditions and technical difficulty, the race has a 32-hour cutoff and serves as a Western States 100 qualifier. It offers a Solo Division for unsupported runners and emphasizes community involvement through mandatory volunteer service or donations. Visit the organization's website for the most recent information.

United States California Julian

Race information

Website Registration
100 mi
15400 m+
100 Miler
Visit the organization's website for the most recent information.
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