Shenzhen is a prefecture-level city in the province of Guangdong, China. A special economic zone, it is located on the east bank of the Pearl River estuary on the central coast of Guangdong, bordering Hong Kong to the south, Dongguan to the north, Huizhou to the northeast, and Macau to the southwest. With a population of 17.5 million in 2020, Shenzhen is the third most populous city by urban population in China after Shanghai and Beijing. The Port of Shenzhen is the world's fourth busiest container port.