Sean o'Brien
Calabasas, United States • 25 Jan 2025
The Sean O'Brien event offers a range of trail running distances including 100K, 50M, 50K, Marathon (26.2 miles), and 30K, taking place in Calabasas, CA. This event is notable as the 100K distance serves as a qualifier for the 2026 Western States 100. Participants can enjoy scenic views along the trails while challenging themselves in various race formats. Registration for the event closes shortly before the race date, ensuring that all interested runners have the opportunity to secure their spot. Visit the organization's website for the most recent information.