The geoglyphs are geometrical, Zoomorphic figures or fitomorfas built in Plains or slopes tended ( usually in deserts of lands to clear ) by addition or accommodation of stones of volcanic origin and darker. The most characteristic of these figures built with a slight undercutting of the soil is that correspond to a single stroke and only you can appreciate its true magnitude from a great height, as they are very large. The best example of the geoglyphs are the Nazca lines.