Miramichi (mĭrəmĭshēˈ) [key], river, c.135 mi (220 km) long, rising in several forks and tributaries in central N.B. and flowing E past Newcastle into the Gulf of St. Lawrence at Miramichi Bay. The bay was visited (1534) by Jacques Cartier, the French explorer. Several Acadian fishing towns are on its shores. The river is noted for its salmon fishing.