Quicksilver Trail Challenge
San Jose, United States • 25 Oct 2025
Event overview
The Quicksilver Trail Challenge is organized by the Quicksilver Running Club of San Jose and is scheduled for Saturday, October 25, 2025, at Almaden Quicksilver County Park in San Jose, California. The event includes the following races:
- Half Marathon
- 10K
- Kids 1 Mile Fun Run (free; kids may register on race morning)
Typical total registration is about 150 runners. Entry fees listed for the event are $60.93 for the half marathon ($71.56 after September 24) and $50.31 for the 10K ($61.43 after September 24). Proceeds from the event are donated to local organizations including the Midpeninsula Regional Open Space District, the Santa Clara Valley Open Space Authority, the Umunhum Conservancy, and AchieveKids schools.
Course, logistics and rules
Runners follow single-track trails and fire roads through the historic Quicksilver mining territory, with views of Mt. Umunhum, the Santa Cruz Mountains, and the Santa Clara Valley. Aid stations on the half marathon are at Capehorn Pass (Mile 3.4) and Prospect #3 (Mile 6.7 and Mile 10.5); the 10K has an aid station at Capehorn Pass (Mile 3.4). Aid station cutoffs are applied at the Randall / Prospect aid station (first and second pass) and at the finish. Race numbers must be worn on the front and cannot be transferred. Pacers, bandits, and pets are not allowed. If a runner drops out, they must report to the scoring table at the finish line. Weather can vary; starting temperatures are commonly 45-60 F and afternoon temperatures 60-90 F. Runners are advised to carry at least one water bottle. Course hazards include poison oak, rattlesnakes, and ticks. Volunteers support aid stations and start/finish operations. Sponsors include Sports Basement and Skratch Labs. Visit the organization's website for the most recent information.