Aroostook County

County in north Maine, USA; area 17,407 sq km/6721 sq mi; population (1990) 86,900. Houlton is its administrative headquarters. Industries include the manufacture of paper, wood products, fertilizer, and farm machinery. It is also noted for its hunting, fishing, canoeing, and lumbering. Its eastern section is a rich agricultural area, and is one of the nation's major producers of potatoes.

Settled largely during the bloodless Aroostook War (1838–39) with Canada, it is the state's largest county, and the northernmost part of the eastern USA; Aroostook borders Canada to the north, west, and east. The Allagash, Aroostook, Fish, Little Madawaska, Machias, Mattawamkeag, Meduxnekeag, and St John rivers all flow through the county, chiefly north and east from the mountainous west. Aroostook includes large tracts of wilderness surrounding lakes and rivers, including the Allagash Wilderness Waterway.