The Appalachian National Scenic Trail, generally known as the Appalachian Trail or simply The A.T., is a marked hiking trail in the eastern United States extending between Springer Mountain in Georgia (Georgia (U.S. state)) and Mount Katahdin in Maine. It is approximately convert2178mikmcrefa long. The path is maintained by thirty trail clubs and multiple partnerships. The majority of the trail is in wilderness, although some portions do traverse towns and roads, and cross rivers.

The Appalachian Trail is famous for its many hikers, some of whom, called thru-hikers (thru-hiking), attempt to hike it in its entirety in a single season. Many books, memoirs, web sites and fan organizations are dedicated to this pursuit. Along the way, the trail passes through the states of Georgia (Georgia (U.S. state)), North Carolina, Tennessee, Virginia, West Virginia, Maryland, Pennsylvania, New Jersey, New York, Connecticut, Massachusetts, Vermont, New Hampshire, and Maine. An extension, the International Appalachian Trail, continues north into Canada and to the end of the range, where it enters the North Atlantic Ocean.

The Appalachian Trail, the Continental Divide Trail and the Pacific Crest Trail form the Triple Crown (Triple Crown of Hiking) of long distance hiking in the United States.