Chengde area belongs to the temperate continental climate and temperate monsoon climate characteristics, long cold and dry winters, by the Siberian cold air, cold wave phenomenon occurs from time to time, scraping the northwesterly winds for a long time, the frost-free period of 140 to 160 days, which is in the latitude (latitude of 41 degrees north) higher than the temperate oceanic climate of the Chengde can not be seen in the European countries, and even the Great Wall south of the wall, the climate has differences with the Chengde. The climate is different from that of Chengde. It seems that the ancient people built the Great Wall, really is a meteorological and hydrological demarcation line.