The terrain of Zhejiang is inclined from southwest to northeast, and the terrain is complex. These mountains form three roughly parallel branches from southwest to northeast. It spans eight river systems: Qiantang River, Oujiang River, Lingjiang River, Tiaoxi River, Yongjiang River, Feiyun River, Aojiang River and Caoejiang River, and consists of plains, hills, basins, mountains and islands. Zhejiang Province is located in the middle of subtropical zone, with a humid monsoon climate and superior natural conditions. By the end of 20 18, there were 1 1 prefecture-level administrative regions in Zhejiang Province, including 1 prefecture-level cities (including sub-provincial cities of Hangzhou and Ningbo), 20 county-level cities, 32 counties and1autonomous counties.