Are they ancient road maps or messages for visiting aliens? Lying at the foothill of Peru's Andes Mountains is the site of one of the world's greatest mysteries. Etched, as if by giants, onto its arid, moonscape plains are immense lines that stretch for miles to form strange shapes recognizable only from the air. Forming the shapes of animals, plants and humans, they were first spotted by pilots in the 1930s, and inspired fantastic expl
