Founders Half Marathon
Race Day Weather
Cold start — layer up
Runners will start in chilly 38°F conditions — dress in layers for the corral and plan to shed early. Temperatures rising to 47°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing.
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Race Info
The Founders Half Marathon is a 13.1-mile out-and-back race in Potomac, Maryland, organized by the DC Road Runners Club. The course runs along the C&O Canal Towpath from the Carderock Recreation Area, with two water stops at Lock 10 and Lock 6 passed twice each. It is race #2 of DCRRC's winter Snowball Series and was known as the Gar Williams Half Marathon before 2025, named for a past president of the club and of the Road Runners Club of America.
