Ultra Running Hub Healdsburg, CA, United States · Saturday, April 10, 2027
Lake Sonoma 100K & 50K
What the course asks
DUV results for the 2026 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.
Typical conditions, April
Regional 2001-2020 average for April — NASA POWER, grid elevation 173 m. Not a forecast.
Results history
| Year | Race | Finishers | Men's winner | Women's winner |
|---|---|---|---|---|
| 2026 | 50km | 218 | Robbie Simpson · 03:39:39 | Hannah Allgood · 04:19:36 |
| 2025 | 55km | 102 | Jacob Banta · 04:21:42 | Joelle Vaught · 05:17:44 |
| 2024 | 55km | 105 | Matthew Seidel · 04:23:09 | Pauline Loulier · 05:00:48 |
| 2023 | 55km | 107 | Benjamin Gallegos · 05:19:32 | Zuzana Trnovcova · 05:20:25 |
| 2022 | 55km | 58 | Timothy Smith · 06:01:59 | Alyssa Clark · 06:05:12 |
The field grew 114% between 2025 (102) and 2026 (218). 39% of the 2026 field were women.
DUV results for the 2026 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.
Course notes
- terrain This is a rolling course. Expect fast, runnable sections where rhythm is key.
- gear With trail terrain, choose a shoe with moderate cushioning for optimal performance.
- nutrition For 100km+ efforts, prioritize real food at aid stations to prevent palate fatigue.
Gear for this race
Chosen for 100 km of trail with 3,200 m of ascent.
- Trail Running Shoes 32 m of climb per kilometre — grip and rock protection before cushioning.
- Race Nutrition Past 100 km the palate quits before the legs do — carry more than one flavour.
- Hydration Vests Pole attachment and chest-strap stability on steep ground.
- Trekking Poles 3,200 m of ascent to walk up.
- Headlamps A 14 h limit puts you out there after dark.
Overview
The Lake Sonoma 100K & 50K will take place in Healdsburg, CA on April 10, 2027. This 100-kilometer trail race covers 3200 meters of elevation gain, which at 32 meters of climb per kilometer makes it a challenging course. The terrain is predominantly single-track trails, making up 86% of the surface, with 9% on dirt roads and 5% on pavement.
With a field bigger than 88% of 100k races, this event draws a significant number of runners. The 14-hour time limit is tighter than 80% of 100k cut-offs, translating to a required pace of 8.4 minutes per kilometer, which leaves less margin for error compared to most other 100k events. The entry fee is US$195.
The race has been held 5 times, starting in 2022, with the latest edition in 2026 seeing 218 finishers.
Similar races
Other 100K trail ultras, closest in distance first.