October is arguably the best time of year to run a half marathon in California. The intense heat of the summer has finally broken, leaving behind crisp mornings and mild, sunny afternoons that are perfect for covering 13.1 miles. Whether you are looking for a flat, fast road race along the Pacific coast, a quiet trail run through ancient redwood forests, or a scenic tour through historic downtowns, California delivers an incredible variety of courses this time of year. With 64 half marathons in California in October, there is a starting line for every type of runner. Whether this is your first half marathon or you are adding another state to your long-term journey, this guide highlights some standout options to help you plan your next adventure. You can also explore all California half marathons to see the full list.
Long Beach Marathon
If you want a flat, scenic road race with plenty of ocean views, the Long Beach Marathon and Half Marathon is a fantastic choice. Taking place on October 11, 2026, this Standout race starts in Downtown Long Beach and takes runners past the historic Queen Mary. From there, you will head through Shoreline Village and run right next to the Pacific Ocean along a flat, paved beach path. It is a highly supportive environment, making it a great pick for first-timers who want a memorable, visually stunning debut. Experienced runners will appreciate the flat profile, which is ideal for settling into a steady, comfortable pace. Running next to the water offers a refreshing breeze that perfectly complements the mild October weather. It is a vibrant, well-supported event that captures the classic Southern California running experience.
2026 Humboldt Redwoods Marathon, Half Marathon, 5K
For a truly awe-inspiring race day, it is hard to beat running beneath ancient giants. The Humboldt Redwoods Half Marathon, scheduled for October 11, 2026, in Weott, offers a flat, USATF-certified road course that winds right through the old-growth redwood trees. This Standout event is famous for its breathtaking scenery—you might find yourself looking up at the towering canopy more than checking your watch. The shade provided by the massive trees keeps the course cool and comfortable, making those 13.1 miles feel just a little bit easier. It is a peaceful, majestic setting that feels worlds away from busy city streets. If you are looking for a race that doubles as a nature retreat, this is a beautiful way to spend a Sunday morning and a deeply rewarding addition to your running journey.
Judgment Day Half Marathon, 10K & 5K Run/Walk
Runners looking for a scenic challenge will find a lot to love at the Judgment Day Half Marathon in Bakersfield on October 4, 2026. This Standout race features a mixed-terrain, hilly course that promises a great sense of accomplishment at the finish line. The route starts and finishes at the historic Sam Lynn Ballpark, adding a fun, community-focused touch to the event. From the ballpark, runners head out the back gate and onto the paved Kern River trail. The varied terrain and rolling hills keep the miles engaging, requiring a bit more strategic pacing than a perfectly flat course. It is a highly regarded route in the valley, offering a supportive atmosphere that makes tackling the hills feel manageable. If you want to test your training and enjoy a well-organized local favorite, this is a great race to circle on your calendar.
2026 - City to the Sea Half Marathon & 5K
Starting with a sunrise at a historic plaza is a pretty incredible way to kick off 13.1 miles. The City to the Sea Half Marathon in San Luis Obispo on October 18, 2026, offers exactly that. This Standout race features a mixed-terrain course that treats runners to a breathtaking point-to-point journey. You will begin at the historic Mission Plaza in downtown San Luis Obispo and make your way toward the coast. Point-to-point races always feel like a true adventure, giving you a real sense of traveling from one distinct place to another. The community support along the way is fantastic, and the changing scenery keeps your mind occupied as the miles tick by. It is a welcoming, beautifully planned event that highlights the charm of the Central Coast, making it a perfect destination race for a fall weekend getaway.
Bizz Johnson
If a fast, scenic trail run is calling your name, the Bizz Johnson Half Marathon in Susanville is a must-do. Taking place on October 11, 2026, this Standout event features a rolling trail course that is famous for its net downhill profile. Running on a trail provides a softer surface that is gentle on the legs, while the rolling downhill sections help you maintain a strong, steady momentum. The course takes you through stunning canyon scenery, surrounded by the changing colors of fall. It is an excellent choice for runners who want to try a trail race without navigating overly technical terrain, offering a supportive, nature-filled experience that feels both adventurous and highly achievable.
Clo Cow Half Marathon
For a race with incredible local charm and a bit of a physical challenge, look no further than the Clo Cow Half Marathon in Petaluma. Scheduled for October 11, 2026, this Standout road race embraces its agricultural roots and offers a hilly, rewarding course through Sonoma County. The rolling hills will test your leg strength, but the sweeping views of the surrounding farmland and vineyards make the effort completely worth it. Petaluma is known for its welcoming community, and that supportive spirit is out in full force on race day. Whether you are an experienced runner looking for a strong training effort or a first-timer ready to conquer some elevation, the fun, relaxed atmosphere of this event makes the miles fly by. Plus, running through wine country in the fall is an experience every runner should have at least once.
MISSION INN RUN
Stepping up to the starting line of a race with decades of history brings a special kind of energy to race day. The 49th Annual Mission Inn Run in Riverside, taking place on October 18, 2026, is a beloved Southern California tradition. This Standout event offers a flat, USATF-certified road course that winds through historic downtown Riverside. Because the course is flat, it is an incredibly welcoming option for first-time half marathoners who want a predictable, manageable route, as well as veterans looking to lock into a consistent pace. The event is deeply tied to the community, serving as a key fundraiser for the Mission Inn Foundation. You will enjoy a highly organized, supportive environment with plenty of cheering spectators. It is a fantastic way to experience the local culture while ticking off another 13.1 miles on your running journey.
Rock 'n' Roll San Jose
If you thrive on high energy, loud music, and massive crowd support, Rock 'n' Roll San Jose is exactly what you are looking for. Scheduled for October 4, 2026, this Standout road race features a flat, USATF-certified course that is perfect for runners of all experience levels. The Rock 'n' Roll series is famous for turning race day into a moving party, with live bands and entertainment stationed throughout the route. This constant stream of distraction is a huge mental boost, especially during the later miles when fatigue starts to set in. The flat streets of San Jose make for a smooth, fast run, allowing you to focus entirely on the fun atmosphere and your own steady progress. It is a deeply supportive, celebratory environment that guarantees a memorable finish line experience.
How to Choose Your October Half Marathon
With so many incredible half marathons in California in October, picking the right one comes down to what kind of experience you want to have. If this is your first 13.1, you might want to lean toward a flat, well-supported road race like the Long Beach Marathon or Rock 'n' Roll San Jose, where the crowds and predictable terrain will help carry you to the finish line. If you are looking for an escape into nature, the towering trees of the Humboldt Redwoods or the soft, rolling trails of the Bizz Johnson offer peaceful, scenic miles. For those who want a bit of a challenge, the hills of Petaluma's Clo Cow Half Marathon or Bakersfield's Judgment Day will give you a great sense of accomplishment. Whatever you choose, remember that training is always easier with support. Find a race that excites you, grab a training plan, and get ready for your next great adventure.