Potomac River Run Half Marathon
Race Day Weather
Comfortable temps, warming through the race
Mild 59°F temps at gun time mean comfortable early miles without overheating risk. Temperatures rising to 72°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 Half Marathon is a single out-and-back along the C&O Canal Towpath, starting and finishing at Fletcher's Cove in Washington, D.C., on the Saturday of race weekend. The course follows the Potomac River upstream to a turnaround about 6.5 miles out, passing historic canal locks and lock houses on a 12-foot-wide crushed gravel trail with no cross streets and no hills. It is USATF-certified and the towpath is shared with other trail users, so runners keep to the right.
