RACE PROFILE

LAKE SONOMA 100K, 50K, TS HALF MARATHON

Geyserville, California·Half Marathon

Next Race · Apr 11, 2026

Join us in Healdsburg, California, on April 11th 2026 for the TERREX Lake Sonoma 100K, 50K, and Trail Sisters Half Marathon! We are excited to have adidas TERREX back as our presenting partner! We are stoked to team up with Mountain Outpost to bring you full livestream coverage, athlete panels, interviews, and commentary from special guests! Lake Sonoma 100K The 100K course will start with a climb up Pritchett Peak with a water only stop at the top. Once you reach the summit you’ll head back dow