Quicksilver Endurance Runs

San Jose, United States • 9 May 2026

Event overview

The Quicksilver Endurance Runs take place on Saturday, May 9, 2026, at the Hacienda Entrance of Almaden Quicksilver County Park (21785 Almaden Road, San Jose, CA). The event includes two distances:

  • 100K
  • 50K

This is the 41st edition of the Quicksilver Endurance Runs and the twelfth edition of the 100K event. The 100K is a Western States 100 qualifying race and is part of the PA/USATF Ultra Grand Prix.

Course, services, and proceeds

Both races run on hilly single-track trails and fire roads. The course passes oak forests, open meadows, and ridges with views of the Santa Clara Valley and the Santa Cruz Mountains. Aid stations are described as fully stocked and staffed by volunteers. Post-race food and a BBQ are provided at the finish. Approximately 50% of race proceeds are donated to non-profits that support youth health programs and trail advocacy projects.

Entry, waitlist, and volunteer information

Registration closes on May 2, 2026. A waitlist is available; a credit card is charged only if a spot opens and the registrant accepts it. Cancelled registrations made before February 9, 2026 are eligible for a 50% rollover of the registration fee. After February 9, 2026 there is no refund or credit. The event relies on more than 100 volunteers. Visit the organization's website for the most recent information.

Race information

100 km
100k
50 km
50k
Visit the organization's website for the most recent information.
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