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Races Clubs Train Wrapped

Cougar Mountain Trail Run Series (October)

Races
United States
Washington
Seattle, WA
Cougar Mountain Trail Run Series (October)

5K Ultra 50K Trail Trail Ultras

Cougar Mountain Trail Run Series (October)

Saturday, October 31, 2026Bellevue, WA5K – 50K

Registration open

Welcome to the 2025 edition of the Cougar Mountain Trail Run Series, put on by Seattle Running Club and Northwest Trail Runs. Our events support King County Parks, with a portion of every entry going to KC Parks. OCTOBER'S RACE ONLY - COSTUME CONTEST/CHALLENGE: The October Cougar Mountain races fall a few days before Halloween so let's see who can get into the spirit and run some trails in costume. UPDATE - there will be an award for best costume (any distance) and best group costume (any distance). Winners will receive a gift certificate and a unique trophy from Otter Pawz Lazer . Oct...

Races

Surface

Trail

Oct 319:30 AM

$40

Oct 319:30 AM

$40

Not affiliated with this event. Official website. We may earn a commission on registrations.

Location

Sky Country Trailhead

Bellevue, WA 98006

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