The Centennial Relay & Ultra Run isn’t just another race. It’s an unforgettable 100K adventure through the heart of the Pacific Northwest!

Covering 100KM (62 miles) along the Centennial Trail, this epic journey starts at Space 802 in Historic Downtown Snohomish, takes runners all the way north to the Nakashima Barn in Arlington, and back to Snohomish for the finish.

Take on the entire 100K solo or build your crew and share the miles with a team of 2, 4, or 6 runners. Whether you're an ultra runner ready to tackle all 62 miles or looking for an unforgettable relay experience with friends, there’s a way to take on the Centennial.

Expect a full day of running, team support, relay exchanges, beautiful Pacific Northwest scenery, and plenty of opportunities to cheer each other on along the way.

Collect the Cowbells 🔔
There are 6 legs to conquer and 7 cowbells to collect!

At the end of each leg, the runner who completed that leg will receive a Centennial cowbell to celebrate the miles they just conquered. Keep collecting them throughout the day as your team makes its way up the Centennial Trail and back.

Your 7th and final cowbell will be waiting at Space 802, where you’ll complete the 100K journey and celebrate at the finish!

For relay teams, the cowbell belongs to the runner who completed that leg, so divide up the miles, collect your cowbells, and see your team’s 100K adventure come together one leg at a time.

Event Details
Distance: 100KM / 62 Miles
Date: Saturday, June 19, 2027
Start & Finish: Space 802, Historic Downtown Snohomish
Course: Centennial Trail to Nakashima Barn in Arlington and back

Race Options:

100K Solo
2-Person Relay
4-Person Relay
6-Person Relay
One trail. 100 kilometers. 7 cowbells. Your challenge, your way.

Grab your crew or take it on solo and get ready for an unforgettable day on the Centennial Trail!