Sanya is the southernmost city on Hainan Island, and one of the four prefecture-level cities of Hainan Province in South China. According to the 2020 census, the total population of Sanya was 1,031,396 inhabitants, living in an area of 1,919.58 km2. Nevertheless, its built-up area encompassing Haitang and Jiyang Districts was home to 801,020 inhabitants as of 2020.