In 13 days · Sat, Aug 8, 2026
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Saturday, August 8th, 2026
Sky Country Trailhead, Bellevue WA
Marathon · 5K
57–79°F · low rain risk
See last 10 years
Rained on 2 of the last 10 race days
2025
50–72°F
dry
2024
54–85°F
dry
2023
61–79°F
dry
2022
60–88°F
dry
2021
53–71°F
rain
2020
56–66°F
dry
2019
57–73°F
dry
2018
61–91°F
dry
2017
59–86°F
dry
2016
54–66°F
rain
Best months to race in Washington →
Race-day forecast · Saturday, Aug 8
Cloudy · 55–77°F
Saturday, Aug 83% chance of rain · wind up to 7 mph
About this race
Race Overview
Welcome to the 2026 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 $15 of every entry going to KC Parks.
Event Schedule
- May 9: 5.1 Miles & 10.8 Miles - 9 AM start for all races, 12:00 PM cut-off (~16:40 pace for 10.8 miles)
- June 13: 5K, 8.2 Miles & 14.5 Miles - 9 AM start for all races, 1:00 PM cut-off (~16:35 pace for 14.5 miles)
- July 11: 5K, 10.8 Miles & 19.5 Miles - 9 AM start for all race, 2:30 PM cut-off (~16:55 pace for 19.5 miles)
- August 8: 5K, 14.5 Miles & 26.2 Miles - 8:30 AM start for the 14.5 and 26.2, 9 AM start for the 5K, 4 PM cut-off (~17:10 pace for the marathon)
Series and Awards
- Series: Best 3 out of 4 races is eligible for awards
- Short Series: May 5.1 Miles, June 8.2 Miles, July 10.8 Miles & August 14.5 Miles
- Long Series: May 10.8 Miles, June 14.5 Miles, July 19.5 Miles, August 26.2 Miles
- Awards: Top overall Man, Woman, and Nonbinary runners based on cumulative time will receive an award and free entry into next year's series.
Discounts and Registration
- Seattle Running Club Member Discount: Contact the race director at races@seattlerunningclub.org to use your membership discount.
- Online Registration: Closes at 11:59 PM PDT the Wednesday before each event
- Day-of Registration: Available for those who did not register in time.
- Cap on Participants: The races tend to sell out, so register early!
Reasons to Sign Up
- Well-marked Trails: Distances that are perfect for all experience levels
- Community: Surround yourself with members of the trail-running community
- Post-race Food: Includes beer provided by one of our Club's partner stores, Flying Lion Brewery
- Support King County Parks: $15/runner donated to the parks
Safety Guidelines
If you are showing symptoms of any illness or disease, please skip this race. Email races@seattlerunningclub.org for other race options or it's a much appreciated donation!
We Run on Native Land
We acknowledge that our running opportunities are built on the purposeful removal of Native peoples, who have been the stewards of Seattle-area lands for thousands of years. Thus, we accept our ethical responsibility for the ongoing stewardship of the land and purposeful support of Native neighbors, colleagues, businesses, and tribes. The Muckleshoot, Duwamish, Stillaguamish, Snoqualmie, and Coast Salish are the Natives of the lands we run on.
Photo Consent
I understand and accept that photos/videos/illustrations may be taken of me and/or my personal property while attending/participating in Seattle Running Club (SRC) events/functions. I acknowledge and agree that such photographs or other illustrations may be used by SRC and its related entities for advertising and promotional purposes in any medium, without compensation to me. If you would prefer not to have a particular photo used, let us know and we’ll do our best to remove it right away.
A Greener Event: Cup Free
Again, this year the series is continuing to reduce the amount of trash created during the event. We ask that runners bring a refillable water container with them on the trail to use at aid stations along the way. Our friends at Seven Hills Running, Fleet Feet Sports Seattle Ballard, and Snoqualmie Running have a variety of hydration products.
Race Information
Thanks to runners like you, the Cougar Mountain Trail Run Series has raised over $265,000+ for King County Parks and contributed hundreds of hours of trail work. Join Seattle Running Club and Northwest Trail Runs in carrying this legacy forward and making this 23rd annual event bigger and better than ever!
Venue Information
Just 15 minutes from Seattle, King County's Cougar Mountain Regional Wildland Park is one of the most popular training grounds for area trail runners and the Seattle Running Club. The course builds on itself throughout the series and brings runners through a lush forest of fern-lined single-track trails, over hills and along marshes and wetland habitats. This is a great series to supplement the training regime for a fall marathon or ultra. Cougar Mountain features rolling hills, a few moderate climbs, and a few steep but short inclines.
No Dogs
As much as we love our four-legged friends and family members, we are not allowed to have dogs at our event. Very important announcement: Dogs are not allowed on the course due to Insurance Requirements.
Awards
The top 3 Men, Women, and Nonbinary Runners in each event will receive a podium prize.
Course map
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