From Stamps of the World
Beihai (Chinese: 北海; pinyin: Běihǎi; Hist: Packhoi) is a prefecture-level city in the south of Guangxi, People's Republic of China. The name of the city means "north of the sea" in Chinese, signifying its status as a seaport on the north shore of the Gulf of Tonkin, which 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.
In addition, it governs the small islands of Weizhou and Xieyang, and is directly west of Leizhou Peninsula. After the 1876 Sino-British Treaty of Yantai, eight Western nations (the UK, US, Germany, Austria-Hungary, France, Italy, Portugal, and Belgium) set up consulates, hospitals, churches, schools, and maritime customs. Its first stamp issues were in 1889 with the use of French Indo-Chine overprinted then surcharged INDO-CHINE.