Western States 100 qualifying 100K. Climbs Pritchett Peak for a sunrise summit, descends to the Lake Sonoma Visitor Center, then runs an out-and-back on the original Lake Sonoma 50 Mile course to a turnaround at Lone Rock.
Not a clean out-and-back: Start -> Pritchett Peak (mile 5.8, water only) -> Woodridge (11.4) -> South Lake (12.7) is a one-way prologue never retraced; South Lake <-> Lone Rock (36.6, the turnaround) is a true out-and-back, mirrored aid-station-for-aid-station; South Lake (60.5) -> Finish (62.1) closes the route without repeating Pritchett/Woodridge. Course chart's cumulative finish mileage is 62.1 mi; the official interactive GPX map (app.racedaymap.com/lake-sonoma) measures 61.9 mi for the same route, a normal GPS-vs-chart variance.
A Western States 100 qualifying 100K, paired with a 50K and the women's Trail Sisters Half Marathon, on singletrack above Lake Sonoma in Sonoma County wine country. The 100K climbs Pritchett Peak for a sunrise summit, drops to the Lake Sonoma Visitor Center, then runs an out-and-back on the original Lake Sonoma 50 Mile course to a turnaround at Lone Rock.
Founded 2008 as the Lake Sonoma 50 Miler by John Medinger and Lisa Henson. New race directors Gina Lucrezi and Justin Keller (Trail Sisters) took over in 2022. The Trail Sisters Half Marathon was added in 2023, alongside a move of the start/finish to the Lake Sonoma Visitor Center and a cash purse for the 50 Mile. Through 2025 the spring event was still 50 Mile + Marathon + Trail Sisters Half. For the 2026 edition, a separate fall race then called the California Fall Classic 100K (also a WSER qualifier) moved to April and was rebranded the TERREX Lake Sonoma 100K; a new 50K was added; the 50 Mile and Marathon distances were dropped from the spring lineup and moved to become the 'OG LS50' inside a new October race, the Sonoma Fall Classic, run by Aravaipa Running with founder Tropical John Medinger. See _meta.notes for the full account and the parts of this history that conflict across the organiser's own pages.
| Mile | Station | Cutoff | Crew | Bag | Pacer | Med | To next |
|---|---|---|---|---|---|---|---|
| 0.00 | Start | ? | ? | ? | ? | ? | 5.80 |
| 5.80 | Pritchett Peak | ? | ? | ? | ? | ? | 5.60 |
| 11.40 | Woodridge | ? | · | ● | ? | ? | 1.30 |
| 12.70 | South Lake | ? | ● | · | ? | ? | 4.60 |
| 17.30 | Island View | ? | · | · | ? | ? | 6.90 |
| 24.20 | Warm Springs | 12:30pm | ● | ● | ? | ? | 5.40 |
| 29.60 | Wulfow | ? | · | · | ? | ? | 2.70 |
| 32.30 | Liberty Glen | ? | ● | ● | ? | ? | 4.30 |
| 36.60 | Lone Rock | 4:15pm | · | ? | ? | ? | 4.30 |
| 40.90 | Liberty Glen | ? | ● | ● | ? | ? | 2.70 |
| 43.60 | Wulfow | ? | · | · | ? | ? | 5.40 |
| 49.00 | Warm Springs | 8:00pm | ● | ● | ? | ? | 6.90 |
| 55.90 | Island View | 10:00pm | · | · | ? | ? | 4.60 |
| 60.50 | South Lake | ? | · | · | ? | ? | 1.60 |
| 62.10 | Finish | 12:00am | ? | ? | ? | ? | ? |
Nobody sees it until we have read it. No account, no sign-in.
This changes nothing on the page on its own. Somebody checks it against the race first.
We want the address of the file the race publishes, not the file. We download it from there so the page can say where the line came from.
We read every one of these and we write back. Every fact here carries the source it came from, and the way a wrong one gets fixed is a person checking it against what you tell us.
NavRun builds your pacing from your own training, then turns it into a plan your crew can follow: when to leave and where to park.
Start free