Introduction to the middle-line scenic spot: The middle-line scenic spot starts from the famous "Longquan Temple" in western Beijing, which is the most complete oriental health culture cultivation group integrating Buddhism and Taoism. Walking along the mountain, you can see the Immortal Cave, Three Buddha Cave, Xuan Xuan Cave, etc. Ancient health-preserving and practicing places such as Yuandong and the Immortal Cultivation Chair have different geographical locations, surrounding environments, and engraved figures. They may represent the four different realms of health-preserving practice of ancient practitioners.