Trail Running calendar near Vacaville 2026-2027

A themed trail event in Cool, California offering 50K, 25K and 10K on marked courses with mapped routes, aid stations, live timing, participant shirts and finisher medals.

A trail race at Bothe Napa Valley State Park on March 21, 2026 offering marathon, half marathon and 10K with a 300 runner limit. Courses use single track loops with one aid station and a six hour marathon cutoff.

A trail event in Oakland through Redwood Regional Park offering distances from a kids 50 yd dash to a 50K. Marked loops, aid stations every 5 to 6 miles, cupless event.

A community fundraiser in downtown Placerville on March 21, 2026 offering live and virtual 5K and 10K options to support New Morning Youth & Family Services and other local nonprofits serving seriously ill children.

A 22.5K event in Clayton, California on March 21, 2026, organized by Nomadic Adventure Club; registration closes March 20 and donations support the club’s free community initiatives.

A charity trail run on March 22, 2026, at Lake Lagunitas near Fairfax, CA. The 10 km course includes technical terrain and ~400 feet of elevation change, with proceeds beyond event costs donated to Evidence Action's Safe Water Now program.

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..

A mostly flat event at Quarry Lakes in Fremont on March 28, 2026 offering half marathon, 10K and 5K distances. Routes follow dirt fire trails with gravel sections and a short paved segment along the Alameda Creek Trail.

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..

Trail races in the Marin Headlands near Mill Valley offering marathon, half marathon and 10K routes on single track and fire roads with views of the Golden Gate Bridge, San Francisco Bay and the Pacific Ocean. The field is limited to 400 pa..

Trail runs on Mount Diablo on April 4, 2026 offering 50K, half marathon, 10K and 5K distances with a portion of fees supporting Save Mount Diablo. The half marathon is included in the Brazen Ultra Half Series.

Trail events on April 4, 2026 from Folsom to Auburn include a 50 mile endurance run plus 25 and 10 mile options, with on-course aid, professional timing, finish medals, goody bags, and post race food and beverages.

The Romancing the Island Half Marathon will take place in Tiburon on Saturday 11 April 2026. You can run between 10 and 21 kilometers.

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.

A multi-distance trail event in Pilot Hill, California on April 11, 2026, organized by Troy’s California Trail Runs, with courses on stony dirt paths across hilly terrain and lake views, offering distances from 5K to 50K.

A four-distance trail event in Calistoga that follows single track and fire road into the Mount St. Helena area. Routes include technical sections, long aid stretches, drop bag service at Highway 29, and finisher medals and shirts.

Run scenic singletrack by Folsom Lake at Outlands Endurance Race in Pilot Hill CA April 18 2026 with 25K, 50K and 50M out and back courses. Includes a hat, wood awards, a post race meal and Sierra Ultra Trifecta credit for 50K and 50M.