Introduction to Wangjing Tower: The 16th watchtower on the east line of the Simatai Great Wall, with an altitude of 986 meters, stands on the top of Laohu Mountain and is the highest point of the Great Wall between Simatai and Gubeikou. Standing upstairs, you can vaguely see the outline of Beijing City, and you can also see thousands of lights in Beijing City at night, hence the name.