Mt. Si Relay & Trail Runs
Snoqualmie, Washington, United States
May, 2027 (TBD)
50k, 50mi, Half-marathon, Marathon, Ultra, Relay
Race Information
The Mt. Si Trail Races began as the “Falls to Gasworks Relay” in 1983, beginning at Mt. Si High School near Snoqualmie Falls and ending at Gasworks Park in Seattle.
Today, the half marathon, marathon, 50K, 50M, and relay are run on the scenic Snoqualmie Valley Trail, with the marathon, 50K, and 50M continuing to run east on the Palouse to Cascades Trail. The trail is old, railroad-grade, with a gentle climb from North Bend to Rattlesnake Lake.
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👍 Run Pick of the Month - Snohomish Women's Run
📍 Everett, WA - May 9, 2026
An empowering, inclusive, and unforgettable Pacific Northwest race!
💸 SAVE 10% On Your Entry. Use Code RG10
Spring Combo: 💸 SAVE 15% when you also register for Tenacious 10
😄 Why We Like This Run
✅ A women-centered run welcoming all genders and abilities.
✅ Fast and flat courses with aid stations and pace leaders for the half-marathon.
✅ Long-sleeve tech hoodie for every runner and supporting local charities.
Run along the scenic Snohomish River in Washington on flat, fast, and well-supported 5K, 10K, or Half Marathon courses, perfect for personal bests or a motivating day on the run.
Take part in this celebration of strength, community, and movement!
🏃 Training for This Race?
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Race Facts
Race Size: 500 - 1,000
Elevation: Fast and Flat
Course Type: Trail
Boston Qualifier: No
Kids Run: No
Where to Stay
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