Where is the hometown of longevity in Hainan?

Chengmai, the hometown of longevity in Hainan, is located in the northwest of Hainan Island, adjacent to Haikou, the provincial capital, across the sea from Leizhou Peninsula, adjacent to Qiongshan City and Ding 'an County in the east, Tunchang and Qiongzhong County in the south, Lingao County and Danzhou City in the west and Qiongzhou Strait in the north. The county has a long history, prosperous humanities, flat terrain, vast and fertile land, with a land area of 206,700 hectares and a usable area of 95.99%. There are still 20,000 hectares of land to be developed. It belongs to the tropical climate zone, with spring-like seasons, abundant rainfall and sunshine.