The Appalachian Mountains, often called the Appalachians, are a vast system of mountains in eastern
North America. Definitions vary on the precise boundaries of the Appalachians. The
United States Geological Survey (USGS) defines the Appalachian Highlands
physiographic division as consisting of thirteen provinces: the
Atlantic Coast Uplands, Eastern Newfoundland Atlantic, Maritime Acadian Highlands, Maritime Plain,
Notre Dame And Megantic Mountains, Western Newfoundland Mountains, Piedmont, Blue Ridge, Valley and Ridge,
Saint Lawrence Valley, Appalachian Plateaus, New England province, and the
Adirondack provinces.A common variant definition does not
include the Adirondack Mountains, which are often said to have more in common with the
Canadian Shield than the Appalachians.