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We are excited to announce that the Lake Sonoma 100K is a 2024 Western States 100 Mile Endurance Run Qualifier!

Western States Endurance Run - 100 Miles - One Day

The Lake Sonoma 100K and 55K are back and brand new for 2023!

Come experience one of the most RELENTLESS and beautiful ultras on the West Coast, with two newly designed new courses that navigate miles upon miles of single track with majestic views of Lake Sonoma, nestled in the beauty of wine country during harvest season. The new fall date will make the LS100 perfect for runners who are looking for a late season challenge, prefer cooler weather, or want to have one last chance to snag a qualifier for the Western States Endurance Run.

The Lake Sonoma Race Series is legendary for its wine country hospitality, and the new race weekend will be no exception. The LS 100K & 55K weekend will be a lively scene for athletes, complete with on-site camping, live music and of course the best local food, wine and beer Sonoma County has to offer! As always, the Lake Sonoma Race Series is a community event, with proceeds from all races supporting the Children of Vineyard Workers Scholarship Fund.

Race Info

Note: it is a good idea to get gas the day before the race as there are no gas stations near the course.

From points south: take Highway 101 north to the Dry Creek Road exit in Healdsburg (65 miles north of the Golden Gate Bridge). Upon exiting, turn left and follow Dry Creek Road for 10 miles. At the end of Dry Creek Road just below the Warm Springs Dam, the road bends sharply left and becomes Stewart Point-Skaggs Springs Road. Look for the Lake Sonoma Visitor Center on your right. The overflow parking lot to the left is the main race parking lot.

From Cloverdale and points north: take Highway 101 south to the Dutcher Creek Road exit. Turn right upon exiting and then immediately left onto Dutcher Creek Road and follow it for 4.1 miles to Dry Creek Road. Turn right on Dry Creek Road and follow it for 1.1 miles. At the end of Dry Creek Road just below the Warm Springs Dam, the road bends sharply left and becomes Stewart Point-Skaggs Springs Road. Look for the Lake Sonoma Visitor Center on your right. The overflow parking lot to the left is the main race parking lot.

From the start to Warm Springs Creek: Return to Stewart Point-Skaggs Springs Road and follow it for 13 miles to the intersection of Old Skaggs Springs Road. Turn right on Old Skaggs Springs Road and follow it for 3 miles to the gate. (Note that this entire 14 miles is on a very scenic country road that twists and turns. If you are prone to car sickness this might possibly be an issue.) Park here and walk a half-mile further down the road to the aid station.

From Warm Springs Creek to Liberty Glen (Madrone Point): Return up Old Skaggs Springs Road for 3 miles to the stop sign. Turn left onto Stewart Point-Skaggs Springs Road and follow it for 11.5 miles to the stop sign at Rockpile Road. Turn left and follow Rockpile Road for 3.2 miles to the Liberty Glen Campground Road. Turn left and follow this for 0.5 miles.

After the entrance station, turn left and follow the road to the Group Campground E. Park here and walk about 200 yards up the service road to the top of the hill to the aid station Allow 45 minutes to drive here from Warm Springs Creek.

Liberty Glen to Lone Rock: Return to your car, and drive back up the hill to Rockpile Road. Turn right and follow Rockpile Road for almost three quarters of a mile back to the Lone Rock trailhead on your left. Please be careful driving this section as the course crosses the road just uphill from the aid station

The Basics

  • NO LITTERING. Zero, zip, nada. Carry it in, carry it out.
  • BE NICE. Be nice to each other, be nice to the volunteers, be nice to other trail users.
  • HAVE FUN!

Violation of rules 1 and 2 will get you disqualified. If you are observed violating rule 3 (i.e., not having fun) we may withhold your post-race beer.

Pacers are allowed in the 100k beginning at the Madrone aid station returning to the start (mile 40). Racers may also pick up a pacer at Warm Springs aid station at mile 48. Multiple pacers are allowed but only one pacer may accompany the racer on the course!

No trekking poles.

Policies

In creating a fair and inclusive event, we believe it is important to provide policies that are clear, accepted, and understood by all who are participating at the event.

Anti-doping Policy

The Lake Sonoma 100k and 55k have a zero-tolerance policy regarding the use of performance enhancing drugs (PEDs). Any athlete who has been determined to have violated anti-doping rules or policies, whether enforced by the IAAF, the World Anti-Doping Agency (WADA), U.S. Anti-Doping Agency (USADA), or any other national sports federation is ineligible for entry into the Lake Sonoma 100k or 55k.

The Lake Sonoma 100k and 55k reserves the right to conduct pre- and post-competition testing for any and all performance-enhancing drugs (PEDs) listed on the current WADA Prohibited List. Any athlete who refuses to submit to anti-doping controls, if selected for testing, shall be disqualified and subject to a lifetime ban from the Lake Sonoma 100k and 55k.

Transgender and Non-binary Entrant Policy

We are utilizing the policy Western States Endurance Run has created, with a few minor edits to fit our event. *Kudos to WSER for taking the helm and bringing awareness and progression.

A male-to-female transgender entrant can register to compete as a female provided the runner has been undergoing continuous, medically supervised hormone treatment for gender transition for at least one year prior to the race.

A female-to-male transgender entrant can register to compete as a male provided the runner has been undergoing continuous, medically supervised hormone treatment for gender transition for at least one year prior to the race.

For transgender entrants who have not been undergoing continuous, medically supervised hormone treatment for gender transition for at least one year prior to the race, please register with the gender that was provided at birth. (For the sole purpose of awards and results.)

Non-binary and non-conforming entrants are recognized as such. We will ask for their birth gender for the purpose of awards and results.

Results Challenges

Result challenges may only be made if the participant in question has placed in the top five or is an age group winner. Challenges are only to be shared with the race director, who will privately speak to the participant in question and also a medical official if necessary. The race director will keep all information and conversation confidential, and will handle accordingly with the utmost discretion based on the situation or question at hand. *Any hateful or discriminatory behavior will not be tolerated.

Refunds & Cancelations

– There will be no deferrals (other than pregnancy deferrals), credits, transfers or waitlists for any race distance.

– Runners who must drop out may do so on or before July 21st and will receive a 50% refund*.

– Runners may move down in distance, provided they do so on or before August 30th.

*Race Processing Fee is non-refundable. Refund will be 50% of Race Cost only.

Pregnancy Deferral

If a woman entrant becomes pregnant after registering for the race, we are happy to allow her to defer her entry to either of the next 2 years of the race.

Race Cancelation

If the race cannot be held on the planned date due to conditions out of the race director’s control, the event will be rescheduled at the race director’s discretion. All race entrants will be automatically registered to the new race date. There will be no refunds given.

Travel Insurance

Entrants are encouraged to consider travel insurance as a way to protect their financial interests in the case they cannot attend or travel to the event due to any unforeseen circumstances.