Knowing that Xu Xiake was very young, he had a dream at that time to play. Xu Xiake is my role model. He made me understand that there is no road longer than feet, no mountain higher than people ... 1586, Xu Xiake was born in a beautiful village in Jiangyin County, Jiangsu Province. He loved reading books on astronomy, geography and famous mountains and rivers since he was a child. At the age of 22, he bid farewell to his family and went out to visit the mountains and rivers of the motherland to explore the mysteries of nature. His footprints spread all over North China, East China, South China and Southwest China, especially his exploration of Southwest China in his later years was more adventurous. /kloc-in the first month of 0/637, Xu Xiake arrived in Hengyang, Hunan. When he was going to visit Maye Cave in Chaling, Hunan Province, the local people told him: "There are dragons and tigers in Maye Cave, and no one dares to enter." Xu Xiake was not afraid, but very happy. He always likes to look for strange and beautiful scenery, so he decided to be the first explorer of Mayadon. Xu Xiake wanted to find a guide to lead the way, but no one dared to take the risk. People advised him: "To tell you the truth, there are dragons and tigers in the cave, and you can't get in without magic." Xu Xiake ignored this superstition. He paid a high price for a guide, but just as he was about to enter the cave, the guide heard that Xu Xiake was a scholar and didn't know magic. He was so scared that he repeatedly said, "Boy! I thought you were a mage, so I dared to show you the way. You are not a mage, and I can't afford to lose my life ... "Say, and turn round and then walk. The news that Xu Xiake is going to enter Maye Cave has caused a sensation among the surrounding villagers. After a while, the woodcutter took the sickle, the farmer took the hoe and rake, the cook stopped the fireworks and the loom stopped. Even the teenage shepherd boy came over curiously and surrounded the hole. When Xu Xiake was ready to go down the hole, the onlookers suddenly boiled. Someone said, "There is a dragon in the cave." Someone said, "There are monsters in the cave, and people who can't spell can't surrender these things." Everyone said a word, I said a word, looked down, and there was no one who was not worried about Xu Xiake. However, Xu Xiake is not afraid. He calmly took off his clothes and went down the hole with a flashlight to explore. In the cave, he not only didn't meet all kinds of legendary dragon monsters, but personally felt another world of "stone illusion, skin change and all kinds". At this time, many people in the village gathered around the hole to see how the devil ate the daredevil. Xu Xiake went into the cave and carefully examined the structure of the cave. No monsters were found. When he walked out of the hole safely, the torch had burned out. People around the hole were surprised and happy, and said, "We thought you were eaten by a monster because you haven't come out for a long time." When Xu Xiake returned to the mouth of the cave after inspection, nearly 100 people who were full of doubts and anxiously waiting at the mouth of the cave immediately surrounded him. Their doubts and worries vanished, and they all admired Xu Xiake's amazing move. Xu Xiake told everyone that there were no monsters in the cave, but various limestone landforms, including stalactites, stalagmites and stone pillars. The climate in the south is humid. When limestone comes into contact with or penetrates into water containing carbon dioxide, a chemical reaction will occur to dissolve limestone. After a long geological age, limestone has been shaped into various peaks, caves, depressions and so on. This has a unified name in geography, called karst landform (formerly known as karst landform). When the local people see the changing terrain, they think there is some evil magic. Xu Xiake solved the doubts in the hearts of local people with personal practice and scientific truth. Xu Xiake's investigation of limestone landforms in southwest China is his greatest contribution to geography. His research achievement "Xu Xiake's Travels" is the most outstanding achievement of China geography in the17th century. He was 150 years earlier than Espel, the first to describe and inspect limestone landforms in Europe, and more than 200 years earlier than Roman, the first to systematically classify limestone landforms in Europe. Therefore, Xu Xiake is unanimously recognized by geographers as the earliest great pioneer in the study of karst landforms in China and even in the world, and his Travels of Xu Xiake is also regarded as the earliest precious document in the study of karst landforms in the world.