Cougar Mountain Trail Run Series
Bellevue, United States • 31 Oct 2026
Cougar Mountain Trail Run Series
The Cougar Mountain Trail Run takes place on October 31, 2026, in King County's Cougar Mountain Regional Wildland Park in Newcastle, WA. Registration and the race start are located at the Sky Country Trailhead off 166th Way SE.
The courses run through forested terrain with rolling, runnable hills and a variety of trails ranging from narrow, technical single-track to wider, groomed paths. Runners pass through lush forest, fern-lined single-track, hill sections and marsh areas about 15 minutes from Seattle.
Available distances and estimated elevation gain:
- 5k (350 feet)
- 7.6 mile (1150 feet)
- 19.5 mile (3700 feet)
- 50k (7200 feet)
Elevation gains are approximate, estimated from a 50-foot contour map and likely within about 10 percent of actual values. For the 50k course a drop bag may be left and will be available at the aid station at Highway 900.
Online pre-registration is available until Wednesday, October 28, and event-day registration is also available. The series has been held for multiple years and its entries have contributed funds and volunteer trail work to King County Parks; $15 of most entry fees and $10 of each 5k entry are designated to support King County Parks. Visit the organization's website for the most recent information.