Introduction to Jiutian Cave: Jiutian Cave is the first of the entire karst cave landscape. It was developed in the Paleozoic Ordovician limestone rock formations 440 to 500 million years ago, but its formation age is only about one million years old. It is one of the most famous caves in my country. The largest Shihua Cave discovered so far is also the best cave landscape museum in China. After visiting Jiutian Cave, Professor Zhu Xuewen, president of the China Cave Research Society, wrote with emotion: "The variety of types and vast area of Jiutian Cave stone flowers are unparalleled at home and abroad." and the reputation of "the best Tianhua Cave in the world".