Introduction to the Moon Tower: The Moon Tower is located on the top of a peak more than 800 meters above sea level, facing an abyss to the north, lush vegetation to the south, and a peak standing abruptly 50 meters to the west. The entire building is square, 15 meters high, 10 meters long from east to west, and 10 meters wide from north to south. All of them are blue brick and white stone structures. They are one of the relatively complete watchtowers that still exist on the Great Wall.