Cougar Mountain Trail Run Series (October) Logo

Cougar Mountain Trail Run Series (October)

Bellevue, WA

Sat, Oct 31, 2026

In 7 days · Sat, Oct 31, 2026

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When

Saturday, October 31st, 2026

Where

Sky Country Trailhead, Bellevue WA

Distances

5K

Typical weather

On this date: rain 5 of the last 10 years

2025

47–58°F

rain

2024

36–50°F

rain

2023

34–57°F

dry

2022

44–52°F

rain

2021

36–58°F

dry

2020

35–53°F

dry

2019

28–49°F

dry

2018

46–55°F

rain

2017

33–56°F

dry

2016

47–53°F

rain

Best months to race in Washington →

Race-day forecast · Saturday, Oct 31

Cloudy · 39–59°F

Saturday, Oct 31starts near 39°F · 9% chance of rain · wind up to 5 mph

About this race

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.  

 

October 7.6-Mile Cross Country // Cougar Cup - The 7.6-Mile Race is a team race - individuals are still eligible to run the 7.6 mile race for podium awards but not the Cougar Cup . The Cougar Cup is open to any team, group or club. In order to participate in the event, teams must sign-up the morning of the race and declare who is on the team. All team members must sign a waiver and list an emergency contact who is not racing. All teams must pay the entry fee of $180. This is a mixed team event and 2 women must score for each team. Teams can consist of 4-6 people with 4 people scoring and 2 displacing. There will be a cup handed out to the winning team. Team captains need to fill out this survey, and communicate information to other team members.

 

Events

May 10: 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 14: 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 12: 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 9: 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)

October 31: 5K, 7.6 Mile Cross Country, 19.5 Miles & 50K
8 AM start for the 19.5 and 50K (7 AM early start will be available), 9 AM start for 7.6 Miles and Cross Country event, 9:30 AM start for 5K, 5 PM Cut-off (~17:25 pace for 50K, ~19:30 pace for early start)

Event-day registration is available starting at 7:00AM

 

Series:
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
Top overall Man, Woman, and Nonbinary runners based on cumulative time will receive an award and free entry into next year's series.

If you are a Seattle Running Club member and want to use your membership discount on the short or long series, please signup for the series using the short pass or long pass and then send the race director ([email protected]) an email with your SRC member number. You will receive a partial refund within 5 business days. For all other races, please use the coupon code given to Seattle Running Club members--if you do not know the member code, please email the race director with your member number to get the code). 

Online registration closes at 11:59 PM PDT the Wednesday before each event. We will have day-of registration if you did not register in time.

 

Reasons to Sign Up:
1) Well-marked trails with distances that are perfect for all experience levels
2) Community: Surround yourself with members of the trail-running community
3) Post-race food and libations, including beer provided by one of our Club's partner stores, Flying Lion Brewery
4) Raise money for King County Parks: $15/runner donated to the parks

 

DID YOU KNOW

That the August Cougar Mountain Trail Run Series 14.5-Mile Race will serve as the USATF PNTF Open and Masters Trail Championships? There is prize money for this event! Additionally, the 5k race serves as the first ever  USATF PNTF Youth Trail Championship!  This was put together by the PNW Youth Trail Project and is the final race of the inaugural PNW YTP Race Series. Both championship races require participants to be members of the USATF organization - you'll need your USATF member number when registering for a championship race. For more information about how to become a USATF member, click here. Please note - the championship races are optional. Anyone can run the 5k or 14.5mi races without being in the USATF PNTF championship. However, if you want that extra shot of competition, prize money (14.5 mile only), and possible bragging rights, become a USATF member today!

 

Safety Guidelines
If you have had COVID-19 symptoms in the last 10 days or have known exposure to someone with COVID-19, please skip this race.

 

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 and post-race. Our friends at Seven Hills Running, Fleet Feet Sports Seattle (Capitol Hill and 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 $250,000 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 21st annual event bigger and better than ever!

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.

 

The summer Short Series and Long Series races are held on the 2nd Saturday of May, June, July, and August. The Fall races are held on the last Sunday in October. Series standings are updated after each month's races and everyone competing in each successive distance is eligible for Series awards. There is a participant cap and the races tend to sell out, so register early! There are NO REFUNDS!

 

Seattle Running Club Discount
If you are a member of Seattle Running Club, you should have received a discount code for 20% in the newsletter. You will need to provide your member number if you use this discount code. There are also many other discounts and benefits for being a member of the Seattle Running Club. 

 

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 USATF Sanctioning and Insurance Requirements. Despite the park's policy on dogs on leashes being acceptable, USATF has determined dogs on course cause a potentially unsafe environment for participants and spectators. We love our dogs and remember Scott's dog Jack attending Cougar races for years and years. But we want to continue hosting races for years to come and need to abide by the USATF rules.

 

Awards
The top 3 Men, Women, and Nonbinary Runners in each event will receive a podium prize. 
Our August 14.5-Mile Race will serve as the USATF PNTF championships. There will be prize money for this event. Prize money will be announced as we get closer to this event.

 

Course map

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