Cougar Mountain Trail Run Series

AUG

8

2026

Trail races at Sky Country Trailhead in Bellevue offering 5K, 14.5 miles, and marathon distances. Organized by Seattle Running Club and Northwest Trail Runs, with $15 per entry donated to King County Parks.

Sat 8 Aug 2026

Bellevue, Washington

Website Registration

26 miles 15 miles 5 kilometers

Always double-check with the organizer's website! This page may contain affiliate links.

Cougar Mountain Trail Run Series (August)

The Cougar Mountain Trail Run Series event takes place at Sky Country Trailhead in Bellevue, WA. It is part of a multi-month trail series organized by Seattle Running Club and Northwest Trail Runs. The series donates $15 from every entry to King County Parks and has raised over $265,000 for park support and trail work.

The course uses single-track trails through forest, marshes, and wetland habitats. Terrain includes rolling hills, a few moderate climbs, and some short steep inclines. The series runs across spring and summer months with an additional set of fall races in October; series awards are based on the best three of four races in a series category.

Race logistics and services noted by the organizer include well-marked trails, aid stations that expect participants to carry refillable water containers, post-race food and beer from a partner brewery, and a cup-free approach to reduce waste. The event enforces a no-dogs policy due to insurance requirements. Awards are given to the top three Men, Women, and Nonbinary finishers in each event. Online registration closes before each race and day-of registration is available when spots remain. Participant caps apply and there are no refunds. Visit the organization's website for the most recent information.