Introduction to the Nihewan Xiaochangliang Site: The Nihewan Xiaochangliang Site is located 500 meters north of Guanting Village, Datianwa Township, Yangyuan County. In 1978, it was established by the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences. Yuzhu, Tang Yingjun and Li Yi discovered and excavated it. More than 1,000 stone tools were discovered, belonging to the small stone tool tradition; animal fossils found in the mountain soil include Sanshi hyena, three-toed horse, three-door horse, woolly rhinoceros, antelope, etc. Its geological age is 1.36 million years ago. As the northernmost witness of ancient human activities in my country, the Xiaochangliang ruins are engraved on the bronze corridor of the China Millennium Monument.