Lag Bon 10K
Fairfax, United States • 22 Mar 2026
Event overview
The Lag Bon 10K is scheduled for March 22, 2026, at the Lake Lagunitas Picnic Area at the end of Sky Oaks Road in Fairfax, California. The event is a trail running fundraiser tied to World Water Day; ticket sales collected in excess of event costs will be donated to Evidence Action’s Safe Water Now program. Registration opens January 1, 2026. Entry is limited to 100 runners, race day registration is not available, and bib transfers are not permitted. The registration fee is $50 and includes an event T-shirt, finisher medal, stickers, and GU energy gels/chews. Registrations after March 6 may not receive the requested shirt size.
Course and logistics
The course is described as moderately challenging and technical, with stairs, bridges, roots, rocks, and some flat trails. Total elevation gain and loss is approximately 400 feet. The Start/Finish is at the Lagunitas picnic area. Aid stations and bathrooms are located after Bon Tempe Dam at about the 3.5 mile point and at the Start/Finish. The event will be held rain or shine and may involve cold, wet, or muddy conditions. There is a two-hour limit to complete the course due to permit restrictions. No dogs or strollers are allowed. Packet pickup is scheduled the day before at the San Francisco Running Company’s San Anselmo location. Prizes are gift cards to the San Francisco Running Company for top three finishers in Men, Women, and Non-binary divisions. Visit the organization's website for the most recent information.