Northwest's Cougar Mountain Trail Series 20 Miler
A classic year-long trail series with distances for all runners, just 15 minutes from Seattle
Overview
The Cougar Mountain Trail Run Series is a longstanding community favorite hosted by Seattle Running Club and Northwest Trail Runs, raising over $250,000 for King County Parks. This August edition features 5K, 14.5-mile, and 26.2-mile options through the lush, fern-lined trails of Cougar Mountain Regional Wildland Park. With rolling terrain, marshes, and dense forest, it’s the perfect challenge for runners of all levels. This race also hosts the USATF PNTF Youth, Open, and Masters Championships.
Course
Courses include a mix of narrow singletrack, wide groomed trails, hills, and marshland
Logistics
Swag & Medals
Well-marked courses
Post-race food & beer from Flying Lion Brewery
Podium prizes for top 3 in each gender category (including nonbinary)
$15 from every entry donated to King County Parks
USATF-sanctioned championship races with prize money (Open & Masters)
Youth competition via the PNW Youth Trail Project
Aid Stations —
5K / Single short loop with 1 aid station
14.5M / 5 aid stations at miles 3, 4.6, 7.1, 10.3, and finish
26.2M / 6 aid stations at miles 5.4, 6.9, 10.7, 14.2, 18.3, 24.8, and finish
Getting There
Parking available at Sky Country Trailhead off 166th Way SE, Bellevue, WA
Coming from I-90 Eastbound, take exit 13, right on Lakemont Blvd SE for 2+ miles, and make a left on Cougar Mountain Way, right on 166th Way SE
Coming from directions from I-405, take exit 10 to Coal Creek Parkway, turn onto SE 72nd Pl → Newcastle Rd → Lakemont Blvd SE, then turn right onto Cougar Mountain Way, then right on 166th Way SE
Driving Directions
Policies
Race Policies
No refunds
Day-of registration available if not sold out
No dogs allowed on course (USATF sanctioning)
Cup-free event; bring refillable bottles or cups
Land Acknowledgement
We acknowledge that this race takes place on the ancestral lands of the Muckleshoot, Duwamish, Stillaguamish, Snoqualmie, and Coast Salish peoples. These communities have been stewards of the Seattle-area lands for thousands of years. We honor their continued connection to this land and commit to responsible stewardship and support for Native neighbors.
About Northwest Trail Runs
Northwest Trail Runs is a beloved race organizer based in Seattle, Washington, offering thoughtfully designed trail running events that showcase the natural beauty of the Puget Sound region. Operated by Meridian Geographics, Northwest Trail Runs emphasizes accessibility, exploration, and flow—creating memorable experiences for both seasoned trail veterans and newcomers alike.
Founded and led by internationally ranked orienteer Eric Bone, the organization is known for its exceptionally well-marked courses, strategic layouts, and creative event design. Whether it’s a quick 5K or a longer adventure through forested hills, each race is meticulously crafted to offer challenge, variety, and delight on the trails.
In addition to its signature trail running series, Northwest Trail Runs is part of a broader suite of outdoor events produced by Meridian Geographics, an organization deeply invested in helping people explore and appreciate the Pacific Northwest’s natural spaces.
For runners looking for expertly managed, beautiful, and approachable trail races, Northwest Trail Runs offers one of the most dependable and inspiring experiences in the region.
Disclaimer
We make every effort to provide accurate and up-to-date information on Kåduka, but details may change. Please always confirm the latest information on the official race website. See something that needs correcting? Send us a note at [email protected]