Introduction to Dongshigou: The two major mountain ranges in the north and south of Aishan gather in the west and gradually spread out to the east, forming a "eight" shape in the middle, covering an area of ​​several square kilometers. The local people call it Dongshigou. Because nine huge loess ridges of different shapes and hundreds of meters long are naturally formed in the valley, resembling nine soaring dragons, it is also called "Jiulong Ditch".