Beihai is a prefecture-level city in the south of Guangxi, People's Republic of China. Its status as a seaport on the north shore of the Gulf of Tonkin has granted it historical importance as a port of international trade for Guangxi, Hunan, Hubei, Sichuan, Guizhou, and Yunnan. Between the years 2006 and 2020, Beihai is predicted to be the world's fastest growing city. Beihai has a large shipyard, but most of the money generated in the city is derived from trade.