Cougar Mountain Trail Run Series

Event overview

The Cougar Mountain Trail Run Series (August) takes place on Saturday, August 8, 2026, in Bellevue, WA at the Sky Country Trailhead (7077 Clay Pit Rd). The event is organized by Seattle Running Club and Northwest Trail Runs. Distances offered in August include:

• 5K
• 14.5 Miles
• 26.2 Miles

Entry fees listed for the August events are $40 for the 5K, $65 for the 14.5 mile, and $80 for the marathon. Each entry includes a $15 donation to King County Parks. There is a participant cap and the event has a no-refund policy.

Course and logistics

Races use single-track trails through Cougar Mountain Regional Wildland Park, featuring fern-lined trails, marshes and wetland areas, rolling hills, a few moderate climbs, and some steep but short inclines. The series is cup-free; runners are asked to bring a refillable water container for aid stations. Post-race food and beer are provided by a partner brewery. Dogs are not allowed on the course. Photos and video may be taken and used by the organizing club for promotional purposes.

Series and awards

The Cougar Mountain Trail Run Series runs multiple events across the year, with summer races on the second Saturday of May, June, July, and August and fall races on the last Sunday in October. Series standings use the best three of four races for awards. The top three Men, Women, and Nonbinary finishers in each event receive podium prizes; top overall finishers by cumulative time receive awards and free entry into next year’s series. Online registration closes the Wednesday before each event and day-of registration is available. Visit the organization's website for the most recent information.