Cougar Mountain Trail Run Series

Bellevue, United States • 8 Aug 2026

Event overview

The Cougar Mountain Trail Run Series (August) takes place on Saturday, August 8, 2026, at the Sky Country Trailhead in Bellevue, WA (7077 Clay Pit Rd, 98006). The event is organized by Seattle Running Club and Northwest Trail Runs. A fixed donation of $15 from each entry is given to King County Parks. There is a participant cap and entries can sell out. The series has a no-refund policy.

Distances and entry

  • 5K
  • 14.5 Miles
  • 26.2 Miles

Prices listed for the August events are $40 for the 5K, $65 for the 14.5-mile race, and $80 for the 26.2-mile race. Registration opens on February 10, 2026; online registration closes at 11:59 PM PDT the Wednesday before each event and day-of registration is available.

Course, series and rules

Races are held on single-track trails in Cougar Mountain Regional Wildland Park, with fern-lined trails, rolling hills, marsh and wetland sections, a few moderate climbs, and some short steep inclines. The August race is part of a multi-month series held on the 2nd Saturday of May, June, July, and August, with fall races on the last Sunday in October. Awards are given to the top three Men, Women, and Nonbinary runners in each event. Dogs are not allowed on the course due to insurance requirements. The event is cup-free; runners are asked to bring refillable water containers for aid stations. Visit the organization's website for the most recent information.

Race information

26 mi
26.2 Miles
15 mi
14.5 Miles
5 km
Visit the organization's website for the most recent information.
Trail runs nearby

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