The North River is a river, approximately 12 miles (19 km) long, in eastern Massachusetts, the United States. It is primarily a tidal river, formed by the confluence of the Indian Head River and Herring Brook. The North River forms the boundary between the towns of Norwell , Pembroke, Massachusetts, Hanover, Massachusetts and downstream, the boundary between Scituate and Marshfield. The river flows into Massachusetts Bay at New Inlet, where it also converges with the mouth of the . The North River area is also known as the "Irish Riviera" due to the large Irish American population that migrated during the 19th century.