At a vastly smaller scale than Stonehenge, stones ground by natural forces to a well-rounded and relatively regular shape can make very distinctive sounds, which you can hear at song of the Atacama Desert dunes in Chile. According to physicist Stephane Doudy of the Centre de la recherche scientifique in Paris, the volume of sand slides can reach a nearly unbearable 110 decibels — on par with a jet engine. For the complete story of how “self-synchronized avalanches turn piles of sand into musical instruments,” check out Dulcet Dunes by Fenella Saunders of American Scientist magazine. What I find fascinating is that it evidently takes a veneer of salt to make sand sing, so if you really want to hear a tune from a dune, head for a desert that spills into the sea.