Springtime in wine country meets ultra running at Lake Sonoma!

On April 11, 2026, athletes will line up amid rolling hills, oak‑dotted ridgelines, and views that stretch toward the lake below. With a Western States–qualifying 100K, a rugged 50K, and a women’s Half Marathon, this event blends serious competition with community celebration.

Lake Sonoma 100K

This Western States qualifying course begins with a demanding climb up Pritchett Peak, where runners are greeted with a sunrise summit. After descending to the Lake Sonoma Visitor Center, the course climbs again to South Lake Trailhead, entering a classic out-and-back along the original Lake Sonoma 50 mile course.

The 100K is relentlessly hilly and remote, with 13 aid stations spaced along the route (8 full, 5 water-only). You’ll run through madrone groves, lakefront paths, and California carpet singletrack that requires mental and physical stamina. Finish under 19 hours to qualify for Western States 2027.

Drop bags are allowed at Woodbridge, Warm Springs and Liberty Glen. Crew support is allowed at South Lake (outbound only), Warm Springs, and Liberty Glen.

Complete info found at the LS100K website

Lake Sonoma 50K

Come run your first ultra at the Lake Sonoma 50k. Starting at the Lake Sonoma Visitor Center, the course opens with a short paved section before turning to rolling singletrack that climbs and dips through forested terrain. Aid stations include South Lake, Island View, Warm Springs, Wulfow, Liberty Glen, and Bummer, before a bridge crossing and screaming downhill lead you to the finish.

The terrain is punchy with relentless up and downs so conserve early to handle the final miles. Finish line festivities await those who conquer the climbs within the generous 11-hour cutoff. Crew is permitted at Liberty Glen. Drop bags are available at Warm Springs and Liberty Glen.

Complete info found at the LS50K website

Trail Sisters Half Marathon

This women’s half marathon event starts at Lone Rock Trailhead and finishes at the Visitor Center. The 13.1-mile route features rolling terrain, lake overlooks, and a community atmosphere that fosters encouragement among all levels. Aid stations appear roughly every 3–4 miles, and runners have 5 hours to complete the course.

Shuttle transportation is provided from the finish back to the start, and finish line drop bags are shuttled for you. Cutoff at Bummer Aid is 12:00PM.

Complete info found at the Trail Sisters Half Marathon website