The trail is a great, cheap, 3 day weekend (or less, depending how fast, and how far you want to go) getaway that runs the length of the C&O Canal, which would have extended to Ohio if it weren't for the railroads. It is primarily flat, with a slight upgrade to Cumberland from DC. The trail is about 183 miles long (one way), and past Great Falls (great scenic point), there are water wells at intermittent trailside campsites, as well as port-a-johns. The water is a little discolored, probably due to rust and iodine used to purify the water - it is safe to drink. The best view I've ever seen from a Port-a-john is a the Paw Paw Tunnel, where the trail goes 3/5 miles through a mountain - have a light - it's longer than it would seem, trust me. Best times to go are late spring, early fall for unreal seasonal color changes - bring a tent, your significant other, maybe a camera, and marshmellows. We rode the trail in a little over 2 days, camped trailside, bathed in the river (really friggin cold water), ate MRE's. There's food in Cumberland, Hancock, and Harpers Ferry primarily - plan to take at least 3 days to really take in all there is to see. Historic Harper's Ferry, the rapids along the Potomac, especially at Great Falls, the museums, canal locks, historic houses, trestles, etc. It's worth it - screw Disney. You can also purchase reading material dedicated to this trail - I'm not exactly a historian. For me, it's a great escape from the concrete jungle I live in. Avoid weekends when it's nice if tourists, and family scrimmage lines on the trails annoy you - up to Great Falls, the trail is very popular. As you head west, watch for deer, black snakes. Bring paniers, and have fun.
The trail terminates at two points; Washington DC at Georgetown (27th and M NW), and Cumberland Maryland on the other end. Depending on where you're starting, use mapquest or similar service.
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