The Allagash River is a tributary of the Saint John River, approximately long, in northern Maine in the United States. It drains in a remote and scenic area of wilderness in the Maine North Woods north of Mount Katahdin. The name Allagash comes from the Abenaki language, a dialect of the Algonquin languages, spoken by the Penobscot Tribe The word, /walakéskʸihtəkʸ/, means bark stream.