Saturday, August 26, 2023 • Seattle, WA • Course Map
Part of a series of running and walking events that take place throughout the summer and fall seasons in Seattle’s Magnuson Park, which lies right on the shores of Lake Washington, the Magnuson Summer Series Fitness Day features five race distances — a 13.1-mile half marathon, 15K, 10K, 5K and a dash run for kids.
The August race follows the same race routes around the winding park roads and trails inside Magnuson Park, to give runners a chance to gauge the progress of their improvement in their fitness levels over the course of the second half of the year.
Organized by Club Northwest, a locally based running club, the events all use the same 5-kilometer course as the baseline route from which all the other events are built upon.
Those running the 5K, for example, run the route a single time, while those running the 10K run it twice, those running the 15k run it three times, and those running the half marathon make four loops around the course, plus an additional one-kilometer stretch near the start & finish line area.
All races start and finish near the parking lot on the western side of the park, which lies along the Lake Washington shoreline.
From there, runners follow a counter-clockwise loop along the roads and trails that wind through this 350-acre park, past the wide-open fields, athletic facilities and past the buildings that once serve as the military headquarters for the naval air station that occupied the land the park now sits on, back in the 1940s.
Race Weather & Climate
Located in northwestern Washington on the ithsmus of land that lies between Lake Washington and Puget Sound, Seattle typically sees some of its warmest and driest weather of the year in August, which has brought record temperatures as low as 48°F (in 1980) and as high as 94°F (in 1996).
On race day (Aug. 26), the average low is 56ºF and the average high is 76ºF.
See race website
To reserve your spot in the 2023 running of Seattle’s Magnuson Series Summer Fitness Day Half Marathon, 15, 10K or 5K race, register online at the event website here.
Official Race Website
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