The National Trail System in the United States spans many thousands of miles of foot trail. The crown jewels of that system, of course, are the Appalachian National Scenic Trail, the Continental Divide Trail, and the Pacific Crest Trail.
While the adventurous might look at those long trails and set their sights on hiking one end from end, not all manage to complete the journey. Many become disillusioned after days spent hiking in the rain, or because they become homesick, or because of the blisters that sprout on their feet.