The city is mostly hilly to the east and flat in the west. It has 115.98 kilometres (72.07 miles) of shoreline. The city centre of Dongguan is 50 kilometres (31 miles) from Guangzhou to its north. 90 kilometres (56 mi) from Shenzhen to its south, 87 kilometres from Hong Kong and 89 kilometres from Macau by water transport. It is located at the middle of the Guangzhou-Shenzhen economic corridor, a transportation hub.