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在远古时代，洞穴是人类最佳的住所。而在今天，洞穴又是人们休闲游览和搜奇探险的理想去处。洞穴还与我国先辈发明火药（大约在公元808年）有密切的关系。因为火药的基本原料硝石就是从洞穴中采集的。我国是一个洞穴大国，早在公元前的数百年，便有有关洞穴的文字记载，是世界
In ancient times, caves are the best place for humanity. Today, caves are the ideal place for leisure and adventure exploration. The cave also has a close relationship with the invention of gunpowder by our ancestors (around 808 CE). Because gunpowder basic raw saltpeter is collected from the cave. Our country is a great cave country. As early as BC, hundreds of years ago, there were written records about the caves and the world