Introduction to Beiyue Palace: Beiyue Palace is surrounded by walls on three sides and built in a huge grotto. Hengshan has been said to have "spiritual stones flying eastward" since ancient times. According to legend, Emperor Shun visited the north and offered sacrifices to Beiyue. It was the middle of winter and the mountain was blocked by heavy snow. Emperor Shun was blocked within the boundaries of Hebei and could not go to the mountain to worship, so he had to offer sacrifices far away in Quyang. During the ceremony, a huge stone suddenly flew down from Hengshan in front of the emperor. He named the stone "Anwang Stone" and built a temple in Quyang to worship it. This is the "Hengshan Lower Temple".