Petroglyphs (also called rock engravings) are images created by removing part of a rock surface by incising, pecking, carving, and abrading. The oldest petroglyphs are dated to approximately the Neolithic and late Upper Paleolithic boundary, about 10,000 to 12,000 years ago, if not earlier.There are many theories to explain their purpose, depending on their location, age, and the type of image. So

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拍攝者： Excentro