The Seneca Creek Aqueduct is located at mile 22.8 of the C&O Canal, and it is noteworthy for a number of reasons. For starters, it is the first of the eleven aqueducts as one heads upstream from Georgetown toward Cumberland, Md. Also, the aqueduct is one of the few that sits beside a lock (Riley’ s Lock, number 24). The only other one I can think of is at Tonoloway Creek–feel free to correct me if I’m wrong. Finally, this aqueduct is missing the upstream arch, as one heads up the Canal. The arch has been replaced by a footbridge that connects it to the remaining arches.
The Seneca Creek Aqueduct is also a popular destination for boaters. It’s not uncommon to see power boats traveling under the arches, nor is it strange to see kayakers practicing Eskimo rolls where the creek meets the Potomac River.