When Thoreau ventured into the Maine woods in 1846, he was one of a handful who did so simply to see what was there. Now, hundreds of thousands of people pursue "the wildest country" either for itself, as Thoreau did, or as the terminus of the Appalachian Trail. Using Mount Katahdin as his lab, Eric Pinder contemplates what draws people to the mountains. Are the urbanites trekking the trails with cell phones, synthetic fabrics, and GPS units having...