The Nazca Lines were unknown in the 1930’s when the highway that stretches from Canada down though the Americas was built. It actually cuts through the edge of the area where the lines are. The lines only became known after the first commercial flights started going over them and the pilots started talking about them. Maria Reiche’s took an interest and she walked the lines and mapped them.
It is believed that they were drawn there by shamans who were sending messages to the gods up in the sky and in the mountains. The Inca actually believed that the gods lived in the mountains and many Peruvians still revere the mountains to this day. Anyway, the lines were drawn so they could only be seen from the sky and, since man could not yet fly, only the gods could see them.
Our guide told us that they were made by scraping the first layer of sand away and exposing another color of sand.