Digong:Dapi Mountain and the Changes of the Yellow River Course in Ancient Times
As one of the landmark of the beginning of the lower reaches of the Yellow River,Dapi refers to Dapi Mountain located in the north of Gongyi and Xingyang of present Zhengzhou.The line between Dapi Moun-tain and Guangwu Mountain from Luokou to Sishuikou has been called Digong since ancient times.This title re-flects the close relationship between the basic flow direction of the first section of the lower reaches of the Yellow River and the supporting role of Dapi Mountain and Guangwu Mountain.More than that,Dapi Mountain is still a natural guarantee for the city safety of Zhengzhou and Huanghuai Plain.