Taishan (Chinese: 台山; Mandarin: Táishān; Cantonese: Toisan; Taishanese: Hoisan, Other: Toishan, Toisaan) is a coastal county-level city in Guangdong Province, China. The city is located in the Pearl River Delta, southwest of Jiangmen (to which it administratively belongs) and 140 kilometers west of Hong Kong, with a population of approximately 1 million. It contains 95 islands and islets, including the largest island in Guangdong, Shangchuan Island. It is one of four county-level cities in an area known as Sze Yup. Because it is estimated that over 75% of all overseas Chinese in North America until the mid- to late-20th century claimed origin in Taishan, the city is also known as the "Home of Overseas Chinese." Taishanese speak the Taishan dialect, a dialect of Cantonese. Before the 1970s, Taishanese was the predominant Chinese language spoken throughout North America's Chinatowns. It is the de facto language of Taishan.