Cougar Mountain Trail Run Series
Bellevue, United States • 13-31 Jun-Oct 2026
Cougar Mountain Trail Runs
The Cougar Mountain Trail Runs are a summer race series held in 2026 as the 23rd edition. The events are organized by Seattle Running Club and Northwest Trail Runs and raise funds for King County Parks, with more than $254,000 donated to date. The series also donates $15 per runner to the parks.
Race formats include multiple distances across the summer months and an autumn race that is not part of the series.
- May: 5.1 miles and 10.8 miles
- June: 5K, 8.2 miles and 14.5 miles
- July: 5K, 10.8 miles and 19.5 miles
- August: 5K, 14.5 miles and 26.2 miles
- October: 5K, 7.6 mile cross country, 19.5 miles and 50K
The Short Series and Long Series span the four summer races. Series scoring counts the best three of four finishes and series awards require finishing at least three races. Online registration closes the Wednesday before each event and in-person registration is available at the starting area. Registration fees are non refundable.
The courses use Cougar Mountain Regional Wildland Park, about fifteen minutes from Seattle, and run on fern lined single track through forest, marsh and wetland habitats. Trails feature rolling hills, some moderate climbs and a few short steep sections. The event is cup free; runners are asked to bring a refillable water container and aid stations are stocked with Skratch hydration products. August includes USATF Pacific Northwest Trail Championships which require a current USATF membership number for championship entries. Dogs are not allowed on course. Photo policies allow event use of images with removal requests considered. Participants with recent COVID 19 symptoms or known exposure should not attend. Visit the organization's website for the most recent information.