The trail measured 2,168.1 miles in 2001. The total distance of the trail changes slightly from year to year as trail maintenance groups reroute the trail as needed. An Appalachian Trail thru-hike takes between five and seven months to complete the entire trail. (About 20 percent of hikers who begin the trail will complete it.) The average cost of an Appalachian Trail thru-hike is approximately $3,000 (about $1.50 per mile), not including gear.