Trail Running calendar near Windsor 2025-2026

We have found 54 Trailruns within 80 miles of Windsor. See below where and when you can find the races.

The Ruth Anderson Memorial Endurance Run is an ultradistance race held annually in San Francisco, California, at scenic Lake Merced. The course features a mostly flat, USATF-certified 4.48-mile loop on paved paths and groomed dirt shoulders around the lake, with about 100 feet of elevation gain per..

Go Wild Marin 4 Hr is an adventurous trail and wilderness scramble held on the Tiburon Peninsula in Corte Madera, California. Participants compete individually or in teams of up to five, using a custom map to locate as many as 24 checkpoints scattered across trails and wild areas within a four-hour..

The Napa Lapa Trail Adventure, held at Skyline Wilderness Park in Napa, California, is a unique time-based trail running event where participants run as far as possible within set time limits of 3, 6, or 12 hours. The course features a challenging 4.16-mile loop with approximately 815 feet of elevat..

The John Lawson Tamalpa Challenge is a cross-country running event held annually at China Camp State Park in San Rafael, California. The 2025 edition features three races, each approximately 4.2 miles long, primarily on rolling single-track trails with a short stretch on asphalt. The event honors Jo..

The Lake Sonoma 100K and 55K, also known as the California Fall Classic, is a challenging ultramarathon held at Lake Sonoma, California, set amidst the scenic wine country during harvest season. The event features two distances—100 kilometers and 55 kilometers—on demanding courses that traverse mile..

The California Fall Classic at Lake Sonoma, held in Healdsburg, CA, offers two challenging ultramarathon distances: 100K and 55K. Set amidst the scenic wine country during harvest season, the courses feature relentless single-track trails with stunning views of Lake Sonoma. The 100K serves as a qual..

The Diablo Summit Stomp is a trail running event held in Walnut Creek, California, featuring distances of 30K, half marathon, 10K, and 5K. The courses traverse dirt trails starting from Castle Rock Park and extend into Mount Diablo State Park, with the 30K reaching the summit of Mount Diablo. The ev..

The Oakland Hills Trail Run, held at Redwood Regional Park in Oakland, California, offers three challenging distances: 10K, half marathon, and 35K ultramarathon. Set in a serene redwood forest with towering 150-foot coast redwoods, the course features technical dirt trails and fire roads with signif..

The Napa Fall Wine Country Marathon is an annual trail running event held at Bothe-Napa Valley State Park in Saint Helena, California. Celebrating its 33rd year, the race offers marathon, half marathon, and 10K distances. The course features lush single-track trails with hills, streams, and rocky te..

November 2025

The Oakland Tech 5km Fundraiser Race and 1 Mile Fun Run/Walk is set to take place at Joaquin Miller Park, supporting the Oakland Tech Cross Country and Track Team. This event features a scenic 5K trail run and a 1-mile fun run/walk, designed to cater to both competitive runners and leisurely partici..

The Lake Chabot Trail Run, held in Castro Valley, California, offers a variety of distances including 8K, Half Marathon, 30K, Marathon, 50K, and a free Kid's Run for children six and under. The course begins at the Lake Chabot Regional Park Marina and loops around the scenic Lake Chabot reservoir an..

The Mt. Tam Trail Run, held at Stinson Beach, California, offers challenging trail races of 10K, half marathon, 30K, and 50K distances. The course features a demanding climb up Mount Tamalpais with stunning views, followed by scenic trails through the Headlands, finishing back at the beach.The terra..

The Golden Gate Trail Classic will take place in San Francisco from Saturday 22 November 2025 to Sunday 23 November 2025. You can run between 15 and 50 miles.

The Quad Dipsea will take place in Mill Valley on Saturday 29 November 2025.

UTMB Index
December 2025

The Peacock Gap Trail Run, hosted by Inside Trail Racing, takes place at China Camp State Park in San Rafael, California. Scheduled for December 6, 2025, the event offers three distances: 10K, half marathon, and 30K, with courses featuring scenic single-track trails, forested areas, and views of Mt...

The Hunter S. Thompson Fear & Loathing is a unique, no-fee urban ultra running event held annually in San Francisco, CA, since 1985. Participants can choose between a 50K or 50-mile single-loop course that starts and finishes at Twin Peaks, offering stunning city vistas.The route covers iconic touri..

The Hark the Herald Half Marathon & 10K is an annual running event held at Angel Island State Park near Belvedere Tiburon, California. Celebrating its 37th year in 2025, the race features a scenic, hilly loop trail around Angel Island with stunning views of the Golden Gate Bridge, San Francisco, Alc..

The Brazen New Year's Eve event, held at Lake Chabot in Castro Valley, California, offers runners and walkers the opportunity to participate in a half marathon, 10K, and 5K trail races. This festive race encourages participants to close out the year with a scenic run on beautiful trails, welcoming a..

January 2026

Brazen New Year's Day 2026 is a scenic running event held at Lake Chabot in Castro Valley, California. Participants can choose from a half marathon, 10K, or 5K race, all set on invigorating trails that welcome the first sunrise of the year. The event offers a festive atmosphere, encouraging runners..

February 2026

Bay Breeze in San Leandro is a scenic running event held at the San Leandro Marina Park along the San Francisco Bay. Scheduled for February 14, 2026, it offers a half marathon, 10K, and 5K distances, welcoming runners and walkers of all levels. The course is mostly flat, hugging the bayside trail an..