Appalachian Trail Connector
Just past Weverton lock, the Appalachian Trail merges with the C&O until Lock 33 where the AT leaves the side of the Potomoc and goes into the town of Harpers Ferry. If you'd like to pick up the AT here, follow the white blazes to the parking lot and under highway 340. It will take you up to 1,250 feet elevation in about a mile and a half. A very different kind of hike than the straight and flat canal. For more info on the Appalachian Trail, you could visit the Appalachian Trail Conference's website but I prefer Kathy Bilton's site. But you can't go wrong with either.
This map (a pdf) will show you where the two trails run. They are each marked as a red dotted line.
This map (a pdf) gives you driving instructions on how to get to Weverton lock & the AT from I-270.
You can enjoy this wonderful view of the Potomac from nearby Weverton Cliffs. To reach it, head north on the Appalachian Trail for about 20 - 30 minutes until you reach a turning point where two trails meet. To the west, the white blazes marks the continuation of the AT. To the east, the blue blazes leads you a short distance to this overlook.