Newcastle upon Tyne (RP: /ˌnjuːkɑːsəl əˌpɒn ˈtaɪn/; Locally: /njuːˌkæsəl əˌpən ˈtaɪn/), commonly known as Newcastle, is a city in the metropolitan county of Tyne and Wear in North East England. It is situated on the north western bank of the River Tyne's estuary and centred 8.5 mi (13.7 km) from the North Sea. Newcastle is the most populous city in the North East region and lies at the urban core of the Tyneside, the seventh most populous conurbation in the United Kingdom and the most populous in the North East. Newcastle is a member of the English Core Cities Group and, with Gateshead, the Eurocities network of European cities.