Seattle Marathon
Race Day Weather
Cold start — layer up
Runners will start in chilly 36°F conditions — dress in layers for the corral and plan to shed early. Moderate humidity at 78% is worth noting for effort level, especially in later miles.
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Race Info
The Seattle Marathon starts at Seattle Center and finishes at Bell Harbor Pier 66 on the downtown waterfront. A new course introduced for the 2025 race takes runners north along Lake Union's Eastlake shore, across the Montlake Bridge, and through Interlaken Park into the Washington Park Arboretum and the University of Washington campus, then west past Gas Works Park and through Fremont before finishing on the waterfront. First run in 1970 by a group of University of Washington friends, it's the oldest marathon in the Pacific Northwest and still pairs a half marathon with the full on race morning.
