 Nevertheless, the name was well established by 12 November 1870 when the Municipal district of Ryde was officially proclaimed.Northern Sydney is described as the area between Port Jackson to the south, Carlingford and suburbs in line with to the west, Hawkesbury River and Pittwater to the north and the Tasman Sea to the east.Northern Sydney is divided into unique regions such as the North Shore (the inner north and norther-western part of the region), Northern Beaches (the northern coastal suburbs to the north-east) and Forest District, a small group of suburbs between the Upper North Shore and the Northern Beaches.