Sean o'Brien
Calabasas, United States • 25 Jan 2025
The Sean O'Brien event offers a variety of trail running distances, including 100K, 50 miles, 50K, Marathon (26.2 miles), and 30K, taking place in Calabasas, CA. This race is notable as the 100K distance serves as a qualifier for the 2026 Western States 100. The event is currently sold out, but interested participants can join the waitlist. The scenic course promises beautiful views and a challenging experience for runners of all levels. Registration for the event closes shortly before the race date. Visit the organization's website for the most recent information.