Dirty December Trail Run

San Diego, United States • 21 Dec 2025

The Dirty December Trail Run, held in San Diego, California, is a festive holiday trail running event featuring multiple race distances: a full marathon, half marathon, 10K, and a unique 6-hour hill climb challenge. The course includes significant elevation gains—approximately 3,500 feet for the marathon, 2,300 feet for the half, and 1,000 feet for the 10K—offering a challenging terrain through scenic trails. Participants are encouraged to run in costumes, with awards for best solo and team costumes adding to the fun atmosphere. The 6-hour hill climb tests endurance on repeated 2.5-mile loops up and down Cardiac Hill, with special King and Queen of the Hill awards. All finishers receive tech shirts and awards, making it a spirited and rewarding holiday trail run. Visit the organization's website for the most recent information.

Race information

42 km
1067 m+
Full Marathon
21 km
701 m+
Half Marathon
10 km
305 m+
10k
Visit the organization's website for the most recent information.
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