Located in the arid Peruvian coastal plain, some 400 km south of Lima, the geoglyphs of Nasca and the pampas of Jumana cover about 450 km2 . These lines, which were scratched on the surface of the ground between 500 B.C. and A.D. 500, are among archaeology's greatest enigmas because of their quantity, nature, size and continuity. The geoglyphs depict living creatures, stylized plants and imaginary beings, as well as geometric figures several kilometres long. They are believed to have had ritual astronomical functions.