Cougar Mountain Trail Run Series

Bellevue, United States • 9 May 2026

Cougar Mountain Trail Run Series (May)

The Cougar Mountain Trail Run Series (May) is a trail running event on May 9, 2026, at the Sky Country Trailhead in Bellevue, Washington. The event is organized by Seattle Running Club together with Northwest Trail Runs and supports King County Parks; fifteen dollars from each entry is donated to the parks.

The event is part of a multi-month series held in May, June, July, and August with additional fall races in October. Series standings use each competitor's best three out of four races for awards. Individual event awards are given to the top three Men, Women, and Nonbinary finishers, and overall top finishers by cumulative time receive awards and free entry into the next year’s series.

Distances offered across the series include:

  • 5.1 miles
  • 10.8 miles
  • 8.2 miles
  • 14.5 miles
  • 19.5 miles
  • 26.2 miles
  • 50K
  • 5K
  • 7.6 miles

The course runs on trails within Cougar Mountain Regional Wildland Park, passing through a forest of fern lined single track, over rolling hills, and along marsh and wetland areas. The route includes moderate climbs and a few short steep sections. The series is cup free; runners are asked to bring refillable water containers. Dogs are not allowed on the course. Registration is subject to a participant cap and there are no refunds. Visit the organization's website for the most recent information.

Race information

11 mi
10.8 Miles
5 mi
5.1 Miles
Visit the organization's website for the most recent information.
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