Prepare for an unforgettable journey through the historic trails of Almaden Quicksilver County Park at the Quicksilver Endurance Runs on May 9, 2026, in San Jose, CA. This renowned event offers challenging 100K and 50K distances, promising an immersive experience amidst the stunning landscapes of peaceful oak forests, wide-open meadows, and ridges with spectacular views of the Santa Clara Valley and Santa Cruz Mountains. The courses, entirely on unpaved single-track trails and fire roads, are known for their significant elevation gains—approximately 13,000+ feet for the 100K and 6,000+ feet for the 50K—making them a true test of endurance and an excellent choice even for a first trail ultra-marathon.

As one of the oldest ultras in the region, celebrating its 42nd edition in 2026, Quicksilver has a storied history and a reputation for its vibrant atmosphere and dedicated community. The 100K race is a qualifying event for the prestigious Western States 100 Mile Endurance Run and a UTMB qualifier. Typical race day conditions in early May feature comfortable highs around 73°F and lows around 52°F, with minimal chance of precipitation, though runners should be prepared for exposed sections that can feel warm. Runners consistently praise the friendly and well-stocked aid stations, offering everything from water and energy drinks to fresh fruit and PB&J sandwiches, ensuring you're supported throughout your effort.

Starting and finishing at the Hacienda Entrance of Almaden Quicksilver County Park, the race culminates in an outstanding post-race barbecue, a fitting reward for conquering the challenging terrain. Beyond the personal accomplishment, participation in the Quicksilver Endurance Runs contributes to a greater cause, with 50% of proceeds benefiting non-profits focused on children's health and trail advocacy. This blend of scenic beauty, a challenging yet supportive environment, and a meaningful mission makes Quicksilver Endurance Runs a standout event on any ultrarunner's calendar.