Appalachian Trail, officially Appalachian National Scenic Trail, hiking path, 2,144 mi (3,450 km) long, passing through 14 states, E United States. Conceived in 1921 by Benton MacKaye, forester and regional planner, and completed in 1937, the trail extends along the ridges of the Appalachian Mts. from Mt. Katahdin, Maine, to Springer Mt., Ga. The largest part of the trail passes through eight national forests and two national parks, but some of its length is still on private property. Hiking and trail clubs maintain shelters and campsites along the path. The Appalachian and Pacific Crest scenic trails, both designated in 1968, were the first two components in the National Trails System. In 1999 the International Appalachian Trail, a 690-mi (1,110-km) extension of the trail north and east from Mt. Katahdin into New Brunswick and Quebec to Cape Gaspé, was dedicated. Sections of this trail pass through Canadian national and provincial parks.

Appalachian National Scenic Trail: see Appalachian Trail.

Appalachian Mountains, mountain system of E North America, extending in a broad belt c.1,600 mi (2,570 km) SW from the Gaspé Peninsula in Quebec prov., Canada, to the Gulf coastal plain in Alabama. Main sections in the system are the White Mts., Green Mts., Berkshire Hills, Catskill Mts., Allegheny Plateau, Black Mts., Great Smoky Mts., Blue Ridge, and Cumberland Plateau. To the E is the Piedmont (foothill) region. The Appalachians, much-eroded remnants of a great mass formed by folding (see mountains), consist largely of sedimentary rocks. Mt. Mitchell (6,684 ft/2,037 m) in North Carolina's Black Mts. is the highest peak.

The Great Appalachian Valley is a chain of lowlands extending S and W from the Hudson Valley; its main segments are the Lehigh, Lebanon, Cumberland, and Shenandoah valleys; the Valley of Virginia; and the Valley of East Tennessee. Long a major north-south travel and settlement corridor, the Great Valley is one of the most fertile areas in the E United States.

The Appalachians are rich in coal; other resources include iron, petroleum, and natural gas. The scenic ranges also abound in resorts and recreation areas, including Shenandoah and Great Smoky Mts. national parks. The Appalachian Trail winds 2,050 mi (3,299 km) along the ridges of the Appalachians between Mt. Katahdin, Maine, and Springer Mt., Georgia.

Crossed by few passes, the Appalachians were a barrier to early westward expansion and played an important role in U.S. history; major east-west routes like the Cumberland Gap and Mohawk Trail followed river valleys or mountain notches. Appalachia is a name applied to parts of the region that were long characterized by marginal economy, isolation of its people from the U.S. mainstream, and distinctive folkways.

Footpath, Appalachian Mountains, U.S. Extending over 2,000 mi (3,200 km) from Mount Katahdin, Maine, to Springer Mountain, Georgia, along the crest of the mountains, the trail passes through 14 states, 8 national forests, and 2 national parks. Hikers and volunteers maintain the shelters and campsites. The trail's highest point is Clingmans Dome (6,643 ft [2,025 m]) in the Great Smoky Mountains. With its first section opened in 1923, the trail was completed in 1937 and became part of the National Trail System established by the U.S. Congress in 1968.

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Mountain system, eastern North America. The Appalachians, among the oldest mountains on Earth, extend almost 2,000 mi (3,200 km) from the Canadian province of Newfoundland and Labrador in the northeast southwestward to Alabama in the U.S. They include the White Mountains in New Hampshire, the Green Mountains in Vermont, the Catskill Mountains in New York, the Allegheny Mountains primarily in Pennsylvania, the Blue Ridge Mountains in Virginia and North Carolina, the Great Smoky Mountains in North Carolina and Tennessee, and the Cumberland Plateau extending from West Virginia to Alabama. Their highest peak is Mount Mitchell in North Carolina. Seealso Appalachian Geosyncline; Appalachian National Scenic Trail.

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