Cougar Mountain Trail Run Series

Bellevue, United States • 31 Oct 2026

Cougar Mountain Trail Run

The Cougar Mountain Trail Run takes place on October 31, 2026, in King County’s Cougar Mountain Regional Wildland Park near Newcastle, WA, about 15 minutes from Seattle.

The event is part of an annual series that has raised over $240,000 for King County Parks and contributed many hundreds of hours of trail work. It offers multiple race distances:

  • 5k – 350 feet elevation gain.
  • 7.6 mi – 1,150 feet elevation gain.
  • 19.5 mi – 3,700 feet elevation gain.
  • 50k – 7,200 feet elevation gain.

Trails feature rolling, runnable hills and a variety of surfaces, from narrow technical single-track to wider groomed trails. The course passes through lush forest, fern-lined single-track, over hills and along marshes. Elevation gains were estimated from a 50-foot contour map and are approximate, likely within 10 percent of actual values.

For the 50k course a drop bag is accepted and will be available at the aid station at Highway 900. Registration and the start are located at Sky Country Trailhead off 166th Way SE; this is not at the Red Town trailhead. Visit the organization's website for the most recent information.

Race information

50 km
50k
20 mi
19.5-Mi
8 mi
7.6-Mi
5 km
Visit the organization's website for the most recent information.
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