Introduction to Jiutian Waterfall: Jiutian Waterfall is one of the six major waterfalls in the underground grand canyon tourist area. Poet Li Bai wrote a poem praising Jiudiequan Waterfall in Lushan Mountain: "The sun shines on the incense burner and produces purple smoke. From a distance, the waterfall hangs in front of the river, and the water flows. Three thousand feet down, it is suspected that the Milky Way has fallen into the sky."