Sonoma Fall Classic
Healdsburg, United States • 17-18 Oct 2026
Sonoma Fall Classic
The Sonoma Fall Classic is a multi-distance trail event at Lake Sonoma in Geyserville, California, held October 17-18, 2026 and presented by Aravaipa Running in partnership with Healdsburg Running Company. The event includes the following distances:
- 100 Mile
- 50 Mile
- Trail Marathon
- 100 Mile and 50 Mile Relays for four-person teams
Courses use extensive singletrack around Lake Sonoma with lake views and sections through wine country during harvest. The 100 Mile is a two-lap 100.5 mile course with approximately +25,058 feet of elevation gain and a 36 hour time limit; pacers are allowed after mile 50 or after dark with a pacer bib and waiver. The Lake Sonoma 50 Mile follows the original South Lake Trailhead start with about +10,612 feet of gain and a 14 hour limit. The marathon covers the classic Lake Sonoma loop at about +5,903 feet and an 11 hour limit.
Aid stations, cutoffs, and crew access are specified for each distance; drop bags are transported to Start/Finish, Warm Springs, and Lone Rock for appropriate distances. Portable toilets are available at Start/Finish, South Lake Trailhead, Warm Springs, Liberty Glen, and Lone Rock. Free on-site camping is offered for registered participants near the start/finish area on a first-come, first-served basis. Packet pickup is scheduled at Healdsburg Running Company on the day before the event. Registration opens January 1, 2026 and closes October 12, 2026. Visit the organization's website for the most recent information.