Trail Running calendar near Alameda County 2026-2027

Scenic trail races in the Marin Headlands on April 4, 2026 feature marathon, half marathon and 10K courses with single track and fire road sections plus views of the Golden Gate Bridge and Pacific Ocean. Field limited to 400 participants.

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.

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

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.

Trail races in April 2026 at Del Valle Regional Park offering Half Marathon, 10K and 5K distances with electronic chip timing. Finisher medals and t shirts are provided and walkers and hikers are welcome.

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.

A community fundraiser at Spring Lake Regional Park on April 18, 2026 featuring a half marathon, 10K and 5K. The low-waste event donates a portion of proceeds to Trione-Annadel State Park and includes a medal, shirt and post-race snacks.

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.

Trail race on Mt Tamalpais with a Half Marathon and 10K on coastal ridge single-track and road, limited to 300 participants, with aid stations, course markings, and participant t-shirts.

Trail running in the Sierra Nevada foothills on April 25, 2026, with 10K, 15K and 30K options over rocky single track and fire roads. The finish area includes food, drinks and race swag.

A 62 mile trail ultramarathon in the Marin Headlands near Stinson Beach, CA, featuring over 11,000 feet of climbing, marked trails and staffed aid stations with medical crews. Entry is limited to 400 runners and a four person relay is offer..

A trail run through the forested Pacific Union College trails in Angwin, California on May 3, 2026, offering a 1 Mile kids run (ages 7 to 12), a 10K and a 26K. The event is cupless and proceeds benefit PUC Athletics.

Trail races from Stinson Beach into Muir Woods include a marathon, half marathon and a 7 mile course. Routes use the Dipsea Trail and Steep Ravine with ladders and stair sections, feature multiple aid stations, and are limited to 300 partic..

Trail race on May 9, 2026 at Lake Anza in Tilden Regional Park offering distances from 10K to 50K plus a free kids 50 yd dash. Courses are marked, aid stations occur every 3 to 4 miles, and the event uses a cupless aid protocol.

A one-day trail running fundraiser on May 9, 2026 in Palo Corona Regional Park with five course options from a 1-mile fun run to a 35k+ route that includes Mitteldorf Preserve.

Trail races on May 9, 2026 at Almaden Quicksilver County Park near San Jose, offering 50K and 100K on scenic single-track and fire roads. The 100K is a Western States qualifier and half the proceeds support local non-profits.

Join the Wine Half Marathon in Napa Valley on May 9, 2026, a 13.1 mile route through vineyards from Rutherford to Yountville. Founded by four French American wine professionals, the race blends warm hospitality, surprises, and scenic trails..

Trailquake stages a half marathon, 10K and 5K on the redwood and pine trails of Sanborn Regional Park in Saratoga, California. Finishers receive custom medals and shirts and volunteer photographers provide free race photos.

Celebrate Mother's Day with a scenic 1K kids fun run plus 5K and 10K at Pinto Lake County Park. Enjoy trails and family fun while supporting Pajaro Valley Shelter Services and local families experiencing homelessness.