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Course & Elevation
The Seattle Marathon's summer half marathon is run on a Saturday in June at Seward Park on Lake Washington, alongside a 5K, a 10K and a kids' fun run. The organisers call it an annual family-friendly run with views of Lake Washington and Mt Rainier, and dogs are welcome. The half marathon is 13.1 miles and starts at 7:00, ahead of the 5K at 8:30 and the 10K at 9:30; only mile markers are placed on the course. The 5K and 10K bundle is run as three laps around Seward Park. At the 2026 race Brian Masterson won the half marathon in 1:07:04, which the organisers announced as a course record. The half marathon entry for the 2027 race was $97 at regular rates. The same organisation also runs the UW Medicine Seattle Marathon and Half Marathon in November.
Weather
Typical climate for the race month — an estimate, not a forecast or a race-day record
June in Seattle is mild and mostly dry: highs average about 22°C and lows about 12°C, with rain on around nine days of the month, and the half marathon starts at 7:00.
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The Race
Seattle
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Course Record
01:07:04
Brian Masterson (2026)
Registration
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Fun Facts
- ▸ Dogs are welcome at the Seattle Marathon summer events at Seward Park.
- ▸ Only mile markers are placed on the course of the summer 5K, 10K and half marathon.
- ▸ Brian Masterson's 1:07:04 in 2026 was announced by the organisers as a half-marathon course record.
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