Alameda County
Trail Running Calendar near Alameda County 2026-2027
Explore the top trail runs near Alameda County for 2026-2027! We've gathered 40 exciting trail runs in the area. Check out our detailed list below to find your next local trail run.
September 2026
A trail running event at Calero County Park offering distances from a kids run to a 50K across single-track and dirt roads, with named aid stations, drop bag support, bib color assignments, and time limits for longer races.
Rocky Ridge in the Las Trampas Wilderness near San Ramon on September 19, 2026 features a half marathon, 10K and 5K on hilly trail terrain with remote runner options.
Historic Bay Area trail event offering 100K, 50 mile and marathon courses, all UTMB indexed with the 50 mile in the Pacific USATF Grand Prix.
Trail running in shaded redwood forest at Sanborn County Park on September 27 2026, with 10K, half marathon and 50K options; steep singletrack, shuttle parking, chip timing and specific mandatory gear for the 50K.
October 2026
21st Annual Garin Park XC Challenge at Garin Regional Park is a USATF Pacific Association cross country meet with about 5K courses featuring hills, scenic views, and a half mile flat finish.
A 12.4 mile loop from Mitchell Canyon to the Mount Diablo summit and back in Clayton, CA, featuring about 4,000 feet of ascent and a five hour cutoff.
A trail race at Almaden Quicksilver County Park with distances from 5K to 50K. Courses are out-and-back, marked with colored ribbons, include aid stations and toilets, and the longer races reach Bald Mountain and Mt. Umunhum.
Trail races in Walnut Creek on October 17, 2026 with distances from 5K to 30K; walkers welcome and courses may include mud and creek crossings.
November 2026
Experience a scenic trail run around the Lake Chabot reservoir and hills. With distances from a 50 yard kids dash to a 50K ultramarathon there is an option for everyone at this Castro Valley event.
A Thanksgiving Day 5K and 1 mile event at San Leandro Marina with canicross teams, kids races, and proceeds benefiting animal welfare; the course is flat with mixed surfaces and free parking is available.
A post-Thanksgiving running event in Fremont offering a half marathon, 10K, 5K, a short kids run, a food drive for the Alameda County Community Food Bank, and a connector medal option.
December 2026
A multi-distance trail event at Calero County Park in San Jose featuring single-track, hills and varied terrain. Aid stations, drop-bag service for the 50K, free parking and support access at Rancho Cañada del Oro are provided.