Introduction to the three-fold ladder: Walking into Yunfeng Mountain, only the "three-fold ladder" that everyone is amazed by is swaying and vaguely hanging on the rock face. More than 2,700 levels of cloud-piercing stone pedals are all carved into the cliffs. They follow the trend of the mountain and lead people to the infinite scenery at an altitude of 2,448 meters. There are forty-three nearly vertical stone stairs carved into a rock near the top of the peak. Visitors need to hold on to the iron chains on both sides to climb up the stairs. When Xu Xiake came here, he heard "thousands of apes singing in harmony". Nowadays, the sound of the ape has disappeared, and the only people who "sing in the meantime" are tourists who scream out of fear or excitement. Fortunately, the escalator is equipped with a climbing chain to ensure that there is no danger.