Quicksilver Endurance Runs

San Jose, United States • 10 May 2025

The Quicksilver Endurance Runs is an annual trail running event held in San Jose, California, featuring 50K and 100K races on scenic, challenging single-track trails and fire roads through oak forests, meadows, and ridges with panoramic views of the Santa Clara Valley and Santa Cruz Mountains. The 100K race is a Western States 100 qualifying event with a 17-hour time limit, while the 50K offers a 4-hour cutoff. Both races emphasize camaraderie, scenic beauty, and supporting non-profit causes that promote children's health and trail advocacy. The event includes fully-stocked aid stations, post-race food, and a vibrant volunteer community. Visit the organization's website for the most recent information.

Race information

100 km
13000 m+
100k
50 km
6000 m+
50k
Visit the organization's website for the most recent information.
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