Macau Peninsula is the oldest and most populous part of Macau. It has an area of 8.5 square kilometres (3.3 sq mi) (4 by 1.8 kilometres (2.5 mi × 1.1 mi)) and is geographically connected to Guangdong province, at the northeast, through an isthmus 200 metres (660 ft) wide. The peninsula, together with the city centre of Zhuhai, sits on an island separated from the continent by distributaries of the Pearl River.