Trail Running calendar near Outer Richmond 2025-2026

The Mt. Umunhum Marathon, Race to the Top and Down, is a challenging trail running event held in Almaden Quicksilver County Park, San Jose, California. This marathon features a rugged course that begins at the Hacienda Entrance and ascends to the summit of Mt.Umunhum, one of the prominent peaks in t..

Rocky Ridge is a trail race set in the Las Trampas Wilderness near San Ramon, California. The event offers a half marathon, a 10K, and a 5K through rugged hills and scenic vistas. The course is demanding and not beginner-friendly, rewarding perseverance with trails and views few runners will see, fo..

The Dick Collins Firetrails will take place in Castro Valley on Saturday 27 September 2025. You can run between 30 and 100 kilometers.

Pacifica Summit Run, staged at San Pedro Valley State Park in Pacifica, California, features 10K and half-marathon trail races hosted by Urban Coyote Racing. Runners enjoy postcard views of the Pacific Ocean coastline and plenty of switchbacks as they ascend the summit on the upper San Francisco Pen..

JP's Backyard Ultra/Hike is a grassroots ultramarathon and hike held at Skyline Wilderness Park in Napa, California. In its third year, the event features a 3.3-mile loop with 550+ feet of climbing through rocky and shaded trails. Runners and hikers may do 1 to 10 loops, starting together on the hou..

Spartan Trail San Jose Challenge takes place at Sanborn County Park in the eastern Santa Cruz Mountains near Saratoga, California, with the race site at West Valley College Parking Lot 5. The event offers three trail distances: 50K, 21K, and 10K. Runners tackle well‑groomed yet steep and difficult t..

The Trailblazer Race in Mountain View, CA, is an annual family-friendly event featuring 10K and 5K runs, plus a 3-mile walk along the scenic Stevens Creek Trail and Shoreline Park. The courses are fast, flat, and stroller-friendly, offering beautiful views of wildlife, salt ponds, and surrounding mo..

The Women's Headlands Half Marathon is a scenic 13.2-mile trail race held annually in the Marin Headlands near Mill Valley, California. Celebrating its third year in 2025, the event features a challenging course with nearly 2,000 feet of elevation gain, showcasing stunning singletrack trails, sweepi..

Star City San Bruno Mountain Half Marathon & 5K, organized by the Excelsior Running Club, takes place in Brisbane, CA, on the San Bruno Mountain trails. The course is 93% on trail with about 2,400 feet of elevation gain, including a single-track downhill and sweeping views of the Pacific, Bay, and S..

The Women's Headlands Half Marathon is a trail running event held in the scenic Marin Headlands near Mill Valley, California. This race features a brand-new half marathon course that highlights the area's stunning singletrack trails, challenging climbs, and exhilarating descents, offering runners a..

The Reservoir Dogs Trail Run takes place at the San Pablo Reservoir / Briones Reservoir area (East Bay Municipal Utility District), Orinda / El Sobrante, CA, on October 4, 2025. Distances offered are: 35K : 23.4 miles, 2,800 ft elevation gain Half Marathon : 13.9 miles, 1,450 ft elevation gain 10K..

Run by the Sea is an annual running event held at Wilder Ranch State Park in Santa Cruz, California. Scheduled for October 5, 2025, the race offers three distances: a 4K run/walk, a 12K run, and a half marathon. The courses primarily follow flat, packed dirt trails along the scenic coastal bluffs of..

The Mt. Umunhum Trail Conquest-Fall is a trail running event held at Almaden Quicksilver County Park in San Jose, California. The race offers multiple distances including a 5K, 7 Mile, Half Marathon, 30K, Trail Marathon, and 50K.The longer courses venture into the scenic Sierra Azul Open Space Prese..

Go Wild Marin offers a trail and wilderness navigation challenge in Corte Madera, California, with 2-hour and 4-hour options. Teams of 1 to 5 use a custom map to locate up to 24 checkpoints scattered along trails and wild areas of the Tiburon Peninsula. The event emphasizes exploration and navigatio..

Ruth Anderson Memorial Endurance Run is an ultramarathon held in San Francisco, California, circling Lake Merced. Runners complete a multi-lap course on a 4.475-mile paved bike path, with aid stations at the start/finish and each loop. The event features distances associated with a 50M designation,..

The event is a time-based trail run held at Skyline Wilderness Park in Napa, California. Runners compete to cover as much distance as possible within a chosen time limit. The event capacity is 400 participants across all options. 12 Hour 6 Hour 3 Hour The course is a loop of 4.16 miles with appr..

The John Lawson Tamalpa Challenge is a three-race cross-country event held at Miwok Meadows in China Camp State Park, San Rafael, California. Each 4.2-mile course follows rolling single-track trails with about a quarter-mile on asphalt, starting near the Miwok Meadows gate and finishing in the Miwok..

The California Fall Classic at Lake Sonoma offers two ultramarathon distances: 100K and 55K, run at Lake Sonoma near Healdsburg, California. The weekend features on-site camping, live music, and local food, wine, and beer, with proceeds supporting the Children of Vineyard Workers Scholarship Fund. R..

The California Fall Classic at Lake Sonoma offers challenging 100K and 55K ultramarathon races set in the scenic wine country of Lake Sonoma, California. Known for its relentless courses featuring miles of single-track trails with stunning lake views, the event takes place in the fall, providing coo..

The Diablo Summit Stomp takes place on October 18, 2025 in Walnut Creek, California (1700 Castle Rock Road). Distances offered are: 30K Half Marathon 10K 5K All distances are run on dirt trails in Castle Rock Park and Mount Diablo State Park. The 30K route reaches the summit of Mount Diablo. Walk..