RacesNorthern California
Lake Sonoma 100K
Demand
3 out of 5
How much it asks
Worth
3 out of 5
Worth the flight + fee
Healdsburg, California, United States
Scorecard · is it worth it?
Strong weekend if you already live nearby.
The card
Lake Sonoma's 50 is retired. We score the 100K that replaced it, because scoring a dead 50 would be nostalgia, and this site is not a museum. The 100K starts toward Pritchett Peak, drops to the visitor center, and runs the old 50's out-and-back along the lake: madrone, singletrack, 13 aid stations, 19 hours if you want a Western States qualifier. Demand is 3. The hills are relentless and the course is remote enough to make people honest. It is not a mountain 100K. Altitude is a talking point only if you have never been to Colorado. The 50 was famous. Fame is not a reason to keep scoring a distance that no longer exists.
Worth is 3, and the tier is regional. That pairing is the point of this batch. If you live in the Bay Area or Sacramento, this is a strong April. If you are choosing a plane ticket, it is not the default. Miwok has the coast. Canyons has the Western States Trail and a circuit tax. Sonoma has oak, a lake, and a wine-country finish that will try to make the 100K feel like a festival. Regional means worth it if you are nearby, not a default plane ticket. Organization confidence is medium. runlakesonoma.com is the public record. The next edition is April 10, 2027. We are not going to pretend the retired 50 is still the product, and we are not going to inflate a qualifier 100K into a destination because the old 50 was famous. If you wanted the 50, it is gone. If you wanted a destination 100K in California, keep reading. If you live nearby, this is the honest local 100K.
Who it is for
Northern California runners who want a hilly WSER-qualifying 100K in April, and who remember the 50 as the race this replaced.
Who should skip
Anyone booking a transcontinental flight for wine-country hills. If you need a plane, Miwok or Canyons are the California 100Ks we would discuss first.
Weekend
Official handbook facts
- Start
- 05:00
- Crew
- 12.7, 24.2, 32.3 mi
- Drop bags
- 11.4, 24.2, 32.3 mi
- Tracker
- Open
Lake Sonoma 100K course details (5am start + crew/drop table) · retrieved 2026-09-06 (repo record)
Field
Last editions · 100K scored distance
Field evidence: who showed up, who finished, how long. DNF is that evidence, not a difficulty score. Public results, scored distance only.
2026
- Starters
- 140
- Finishers
- 97
- DNF
- 31%
- Win
- 8:36:09
- Median
- 15:50:03
2025
- Starters
- 274
- Finishers
- 218
- DNF
- 20%
- Win
- 10:04:00
- Median
- 15:53:28
2024
- Starters
- 286
- Finishers
- 176
- DNF
- 38%
- Win
- 9:59:30
- Median
- 16:22:49
Latest median 15:50:03 (2026) vs the 19-hour cutoff already listed in Gate. Not a hardness score.
Overall field only. Not a pro or sponsored subset.
Climate
Typical April at the start area · historical race-week weather
- Typical high
- 71°F (22°C)
- Typical low
- 48°F (9°C)
- Typical precip
- 1.8 in (47 mm) / April
- Days with rain
- 17% of days
- High point
- 1,969 ft (600 m)
2015–2024 April means at the start / massif. · Open-Meteo ERA5 / climate · retrieved 2026-09-06 (repo record)
Map
Dimensions
Ten 1–5 scores with a one-line why. Organization has a separate confidence tag.
Supporting dimensions · organization confidence medium
The 50 is retired. We score the 100K successor: hilly, remote, 19 hours for a States qualifier.
Relentlessly hilly, not alpine. The climbing adds up; it does not look like a 14er.
Madrone, lake trail, California carpet singletrack. Technical enough, not skyrunning.
April in Sonoma: spring, possible heat, not a monsoon or a freeze.
Wine country hills. The air is not the race.
Healdsburg is easy. That is why this is regional, not a default flight.
WSER qualifier, competitive spring field. Not an icon.
Public schedule, aid map, qualifier rules. Competent local classic.
A spring 100K you drive to from the Bay. Worth 3 is the nearby-not-plane-ticket score.
Oak, lake, Pritchett sunrise. Pretty. Not Marin Headlands, not the San Juans.
| Dimension | Score | Why |
|---|---|---|
Distance & format How much does the advertised distance and format actually ask? | 3 out of 5 | The 50 is retired. We score the 100K successor: hilly, remote, 19 hours for a States qualifier. |
Vertical How serious is the climbing, not just the mile marker? | 3 out of 5 | Relentlessly hilly, not alpine. The climbing adds up; it does not look like a 14er. |
Technicality Hands, poles, route-finding, or just a long dirt road? | 3 out of 5 | Madrone, lake trail, California carpet singletrack. Technical enough, not skyrunning. |
Climate Heat, monsoon, ice, or a friendly summer afternoon? | 3 out of 5 | April in Sonoma: spring, possible heat, not a monsoon or a freeze. |
Altitude Does the air change the race, or is it a talking point? | 1 out of 5 | Wine country hills. The air is not the race. |
Logistics How hard is the weekend around the race: travel, crew, lodging, rules? | 2 out of 5 | Healdsburg is easy. That is why this is regional, not a default flight. |
Prestige & field Does the start list and history change what the weekend feels like? | 3 out of 5 | WSER qualifier, competitive spring field. Not an icon. |
Organization From public evidence, does the event look competently run? | 4 out of 5 | Public schedule, aid map, qualifier rules. Competent local classic. |
Value Entry fee, travel tax, and lottery friction versus what you get on course. | 3 out of 5 | A spring 100K you drive to from the Bay. Worth 3 is the nearby-not-plane-ticket score. |
Adventure & scenery Would you fly for the place even if nobody kept score? | 3 out of 5 | Oak, lake, Pritchett sunrise. Pretty. Not Marin Headlands, not the San Juans. |