Northwest Branch Saint John River

The Northwest Branch Saint John River (French: Décharge du Lac Frontière) is a 15.5-mile-long (24.9 km) river primarily in Aroostook County, Maine, USA. Its origin (46°42′04″N 69°59′55″W) is Frontier Lake (Quebec-Maine) in Quebec, Canada. After crossing the Canada–United States border, the Northwest Branch runs south close to the border until it picks up its tributary, the Daaquam River, which also flows out of Canada.

Source: Wikipedia — Northwest Branch Saint John River (CC BY-SA 4.0)