In the early twentieth century it was believed that such a perfect cone could only have been built by man. But Cono de Arita is natural and believed to be a small volcano which lacked strength to burst through the curst and so never threw lava or developed a crater. Everything around the cone is black salt brought to the surface by ancient magma flows underground. According to the archaeological remains found in the cone, the place was a ceremonial center prior to the arrival of the Incas.
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