There's a thread elsewhere about whether or not a compass is necessary on the AT. I'll bet folks have stories to share about being disoriented on the trail, and perhaps even walking the wrong way (by accident.) I can't remember if that ever happened to me, but I do remember a few occasions wondering whether I was in fact walking in the right direction. Usually on cloudy days, flat terrain, where the trail is twisting and turning, and no views of the horizon.