Guangzhou, China, known historically as Canton or Kwangchow, is the capital and largest city of the Guangdong province, People's Republic of China. Located on the Pearl River, about 120 km (75 mi) north-northwest of Hong Kong, Guangzhou is a key national transportation hub and trading port. It is the third largest Chinese city. As of the 2010 census, the city had a population of 12.78 million. In 2008 Guangzhou was identified as a Beta World City by the global city index produced by GaWC.