 It consists of the five metropolitan boroughs of South Tyneside, North Tyneside, City of Newcastle upon Tyne, Gateshead and City of Sunderland.It is bounded on the east by the North Sea, and has borders with Northumberland to the north and County Durham to the south.Prior to the 1974 reforms, the territory now covered by the county of Tyne and Wear straddled the border between the counties of Northumberland and Durham, the border being marked by the river Tyne; that territory also included five county boroughs.