Calero Trail Run - Winter

San Jose, United States • 6 Dec 2025

The Calero Trail Run - Winter takes place at Calero County Park in San Jose, California, offering a variety of distances including 50K, trail marathon, 25K, half marathon, 15K, 10K, 5K, mile, and a kids run. The course features challenging single-track trails, hills, dirt paths, oak trees, and panoramic vistas, making it an excellent training ground for events like the Western States. The 50K route includes exposure and heat training elements. The event provides marked courses, aid stations, and commemorative medals for finishers. Registration and bib pick-up occur on race day, with detailed course maps available online. Visit the organization's website for the most recent information.

Race information

50 km
50k
26 mi
Trail Marathon
25 km
25k
13 mi
Half Marathon
15 km
15k
10 km
10k
5 km
Mile
Kids Run
Visit the organization's website for the most recent information.
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