Four. Baoting Li and Miao Autonomous County, which belongs to Hainan Province, is located at the southern foot of Wuzhishan in the southern inland of Hainan Province, bordering Lingshui Li Autonomous County in the east, Sanya City in the south, Sanya City in the west and Wuzhishan City in the north. There are four service areas from Baoting to Haikou, namely Donghong Service Area, Ding 'an Service Area, Furenpo Service Area and Longqiao Service Area. Expressway, the eastern route of Haikou, is expressway, Hainan Province, China. It is the Hainan section of Tongjiang-Sanya Highway, the original trunk line of "five verticals and seven horizontals" national highway, and it is one of the components of expressway, the ring road of Hainan area of China National expressway Network.