Lake Sonoma • 100K, 50K, TS Half Marathon

Saturday, April 11th 2026

100K & 50K in April • Read the Press Release

About the Event

Join us at Lake Sonoma on Saturday, April 11^th, 2026, for our springtime ultra trail festival! Our 100k course is a Western States Qualifier that includes sunrise summit views at the top of Pritchett Peak, stretches of trail through enchanting Madrone groves, all along the OG 50 Mile out and back course. Not quite ready for 100k but eager to join the ultra-distance race club? Our all new 50k course provides a taste of the relentless trails that make Lake Sonoma so enticing and rewarding, with a bonus crossing of the iconic Lake Sonoma bridge. Both courses highlight that buttery California carpet, provide outstanding views of Lake Sonoma, and offer professionally run aid stations from the friendliest volunteers you’ll meet! To top it off, finishers receive a custom bottle of wine from Wilson Winery as their award, functional for a well-deserved celebration!

Ladies, in addition to the 100k and 50k we are excited to provide you the Trail Sisters Half Marathon a women’s only race. This fun and challenging race event fosters camaraderie and empowerment through a celebration of participation for first-timers and experienced runners. The point to point course begins at Lone Rock, traversing out and back to the lake, taking runners across the famous Lake Sonoma bridge, concluding at our festival finish line. Trail Sisters race events are known for their supportive environment, and a welcoming field of women providing each other motivation to reach the finish line. Our finish friendly cut off of 5 hours gives everyone the opportunity to cross the finish line.

We are proud of our event offerings, but what brings us the most joy is creating a weekend of community connection and celebration. Activities begin on Thursday afternoon with a shakeout run to Coyote Sonoma, athlete panel and community dinner on Friday, and finally a celebration social with wine tastings at Coyote Sonoma on Sunday at noon.

We hope you will join us this April at the TERREX Lake Sonoma 100k, 50k or Trail Sisters Half Marathon. Come to enjoy event and accomplish your spring time goals, stay to celebrate and experience what wine country has to offer.

Registration

Distance	Oct 1 – Dec 31st	Jan 1st – Apr 5th
Race fee does not include processing fees, taxes or other add-ons.
100k	$280	$300
50k	$185	$200
TS Half Marathon	$110	$115

Finish the 100k in less than 19 hours for a 2027 Western States qualifier.

Presenting Sponsor

Location

Lake Sonoma is surrounded by world famous vineyards and land that is rich in history. Created by the construction of Warm Springs Dam in 1983, the lake provides for flood control, irrigation and recreation. When full, the lake has a surface area of more than 2,700 acres and 50 miles of shoreline, forming the perfect setting for a wealth of recreational activities.

The Lake Sonoma 100k, 50k and start and finish at the Lake Sonoma Visitor Center. (View on Google Map)

The Trail Sisters Half Marathon will start at the Lone Rock Parking Lot and finish at the Visitors Center. There will be a shuttle from the finish back to Lone Rock.

Directions

From Healdsburg, California take Dry Creek Road 10 miles out to the lake. (Google Directions)

From San Francisco head north on 101 and take exit 505 and head northwest on Dry Creek Road. (Google Directions)

From Sacramento take I-80 West to CA-37 W (exit 33B) and then get on 101 N in Petaluma follow that north to exit 505 and head northwest on Dry Creek Road. (Google Directions)

Airports

Sacramento International and San Francisco International are both good options.

Sacramento International is 128 miles away and takes about 2 and a half hours.

San Francisco International is 94 miles away and takes about 2 hours. (But might have more traffic during bust times)

Parking

100k and 50k Race Day parking will be in the 2 large visitors center lots.