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C&O Canal 100

Knoxville, United States • 25 Apr 2026

C&O Canal 100

The C&O Canal 100 is a 100 mile ultramarathon held in Knoxville, Maryland. The course runs largely on the historic C&O Canal towpath along the Potomac River and stretches between Antietam and Brunswick. The event starts at Camp Manidokan and follows riverside terrain with views of the Appalachian foothills.

The race format is one roughly 40 mile loop followed by two roughly 30 mile loops. Nearly every mile of the route stays close to the water. The course is described as low elevation with smooth surfaces, typical of spring conditions in April.

Organizers place approximately seven aid stations along each loop, some of which are visited multiple times. Reported distances between aid stations range from 3 to 6.9 miles. Aid stations are stocked to support runners throughout the loops.

This event is listed as a WSER 2027 qualifier. Registration for the listed edition closes on April 17 at 11:59 PM Eastern Time. The race location and meeting point are given as Camp Manidokan, 1600 Harpers Ferry Road, Knoxville, MD. Visit the organization's website for the most recent information.

United States Maryland Knoxville

Race information

Website Registration
100 mi
100 Miles
Visit the organization's website for the most recent information.
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