The city of Dongguan is located about 60 kilometers east-southeast of the capital city, Guangzhou, Guangdong Province, which places the city on the eastern side of the Pearl River, along with the cities of Shenzhen and Guangzhou, while the city of Zhongshan, across the Pearl River Estuary from the city of Shenzhen, lies on the western side of the Pearl River. In fact, the cities of Dongguan, Zhongshan and Shenzhen form an almost perfect triangle, with Dongguan at its apex, albeit, displaced slightly eastward of the apex of the perfect traingle formed by these three cities. The city of Dongguan has a history stretching back some 1700 years to the first large migration of Han Chinese people to present-day Guangdong Province, as the next section explains.