Gansu is an important province in northwest China. it is situated as geographical center, on the middle and upper reaches of the Yellow River and the Yangtze River, and at the juncture of the Loess Plateau, Inner Mongolia Plateau and the Qinghai Tibet Plateau. Under the provincial administration, there are 12 prefecture level cities of Lanzhou, Tianshui, Baiying, Jinchang, Jiayuguan, Qingyang, Pingliang, Zhangye, Jiuquan, Dingxi and Longnan, two autonomous prefectures of Linxia and gannan, 4 county level cities, 59 counties, 7 ethnic minority autonomous counties and 17 districts under city jurisdiction. Gansu has a dry climate with plenty of sunshine, strong radiation and the temperature varies greatly from day to night. The annual average temperature is between 0℃ -14。C dropping from the southeast to the northwest. It is 4℃-9℃ in Hexi Corridor, 0℃-6℃ in Qilian mountainous area, 5℃-9℃ and 7℃-10℃ in Longzhong and Longdong respectively. Gansu has rich solar energy resources with an annual sunshine time of 1,700-3,300 hours, increasing from the southeast to the northwest. Gansu is one of the birthplaces of the Chinese nation and ancient Chinese civilization. In history, the world famous Silk Road traverses the whole province, thus made the province the earliest place opening to the outside world for economic and cultural exchanges between the east and the west as well as exchanges between different nationalities. There are over one thousand scenic spots in Gansu, including the world famous Dunhuang Mogao Cave, Jiayu Pass, etc.