Halloween Havoc 5k, 10k, And Half Marathon

Experience thrills and chills at the Halloween Havoc in Fountain Valley, Orange County on October 26, 2025! Choose from the 5K, 10K, or push your limits with the exhilarating Half Marathon starting from Mile Square Park. Enjoy a festive atmosphere with Halloween candy, spooky music, and surprises at the finish line. The day begins with bib pick-up at 7:00 AM, followed by the Half Marathon at 7:30 AM and the 5K & 10K shortly after at 7:45 AM. Whether a seasoned runner or out for a fun day, the looped courses offer an unforgettable experience with on-course support, water stations, and restrooms. Dress up in your best costume and join the community for a day of fitness and fun at Halloween Havoc – where every step is a celebration!