Trail Running calendar near Fairfield 2026-2027

A half marathon on March 22, 2026 in La Honda, California, the Horseshoe Lake course runs through Skyline Ridge Open Space Preserve with ocean and bay views. The trail mix and 2230' ascent support The Hatuey Project with entry fees matched..

Join the Western Pacific event on a mostly flat course in Fremont, California. Run on historic trails along Alameda Creek, starting and finishing at Quarry Lakes. Choose from the half marathon, 10K, or 5K distances.

A trail race on March 28, 2026 at American River Overlook Park offering 5K, 10K, Half and 35K routes on Western States trail sections, with technical single-track, major climbs, cupless aid stations, chip timing, and a 400-runner capacity.

Trail races along single track by Folsom Lake on March 28, 2026, with 5K, 10K, 8 Mile and half marathon options. Courses feature dirt and rock surfaces, rolling hills, marked navigation and aid stations, and a commemorative medal for finish..

Explore the scenic trails of the Golden Gate Headlands. This event offers a marathon, half marathon, and 10K distance on April 4, 2026.

The Diablo Trails Challenge offers four trail distances on Mount Diablo. A portion of entry fees supports the conservation work of Save Mount Diablo. The half marathon is part of the challenging Brazen Ultra Half Series.

The American River Endurance Runs offer three distances: 50, 25, and 10 miles, all finishing in Auburn. The 50-mile race is one of the largest of its kind in the US. Runners are supported with aid stations and celebrated at the finish with..

Run a scenic, hilly loop around Angel Island with views of the Golden Gate Bridge and San Francisco Bay. The event includes a half marathon and a 10K, with ferry transportation from Tiburon included in the entry fee. Participation is limite..

Springtime trail races at Lake Sonoma on April 11, 2026 feature a Western States qualifying 100K, a 50K that crosses the Lake Sonoma bridge, and a women-only Trail Sisters half marathon with shuttle service.

Multiple marked trail distances circle Lake Chabot reservoir in Castro Valley, from a free 50 yard kids dash to a 50K. Aid stations occur every 4 to 5 miles and the event operates cupless, so bring a personal cup or soft flask.

A women focused 10K in Auburn on April 11, 2026 featuring scenic trail loops, finisher shirts, age group awards and a raffle with four winners earning a trip to a women only running camp in Spain.

Explore the rolling hills of Cronan Ranch at the Magnolia Magic River Trail Run. This event offers a range of distances on dirt and rock trails, from a 5K to a 50K ultra. All participants receive a medal and access to aid stations along the..

Event Overview The Calistoga Mountain Run is a trail running event with distances of 50k, 35k, a half marathon, and a 10k. It starts in downtown Calistoga, California. The routes take runners onto trails and into Robert Louis Stevenson Stat..

The Outlands Endurance Race takes place on scenic trails at Folsom Lake's Peninsula Campground. Choose from 25K, 50K, or 50 mile distances on runnable single and double track. All runners get custom swag and a post race meal.

Run the scenic trails at Lake Del Valle Regional Park in Livermore. The Badger Cove event offers a Half Marathon, 10K, and 5K on April 18, 2026, with walkers and hikers welcome. The half marathon is part of a challenging trail series.

Trail race at Skyline Ridge Open Space Preserve on April 18, 2026 offering distances from a kids 50 yard dash to a 50K. Routes run mostly on the Bay Area Ridge Trail with marked aid stations and a cupless hydration policy.

Run for a cause at the Annadel Half Marathon in Santa Rosa's Spring Lake Regional Park. Choose from a half marathon, 10K, or 5K on scenic trails, with proceeds supporting Trione-Annadel State Park. It's a low-waste event featuring a race me..

A trail running event in San Carlos on April 18, 2026 offering 1K kids, 5K, 10K and a new 15K with substantial climbing through Big Canyon Eaton and Pulgas Ridge. Festival atmosphere at Crestview Park with timed results and awards.

Trail races through Huddart County Park and Purisima Creek Redwoods on April 18, 2026, offering 10K, half, 35K and 50K courses with chip timing and marked aid stations. The event is limited to 450 runners and is a cupless format.

About the event The Canyons Endurance Runs by UTMB is an event in the historic gold-rush town of Auburn, California. It takes place in the northern California foothills of the Sierra Nevada range. The event is described as taking you back t..