Cougar Mountain Trail Run Series #3

Newcastle, United States • 12 Jul 2025

The Cougar Mountain Trail Run Series #3 is a trail running event held at King County’s Cougar Mountain Regional Wildland Park in Newcastle, Washington, just 15 minutes from Seattle. Scheduled for July 12, 2025, the race offers three distance options: 5k, 10.8 miles, and 19.5 miles. The course features a variety of trails, including rolling hills, narrow technical single-track, wide groomed paths, lush forests, fern-lined routes, and marshside scenery. This event is part of a long-standing series that has raised over $250,000 for King County Parks and involves significant trail maintenance efforts. It is organized by Seattle Running Club and Northwest Trail Runs, fostering a supportive and scenic trail running atmosphere. Visit the organization's website for the most recent information.

Race information

19 mi
19.5 Miles
10 mi
10.8 Miles
5 km
Visit the organization's website for the most recent information.
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