In a number of locations across the islands of Malta and Gozo in the Mediterranean sea there is a complex network of parallel tracks cut into the limestone rocks that are apparently man-made. They are called “cart ruts” because of their resemblance to tracks left by carts.
The tracks are up to 60 cm deep and have an average distance of 110 to 140 cm between them. The age and purpose of the tracks are still a mystery, but it’s generally presumed the ruts formed around 2,000 BC after new settlers came over from Sicily to start the Bronze Age in Malta.
Tracks like the cart ruts at Malta and Gozo are present on other places in the world such as in Sardinia, Sicily, Italy, Spain, Greece, France and Germany. Not all are of the same origin and not all had to fulfill the same purpose. Some are built with stone brick gutters, some are weathered wagon tracks and some grooves caused by natural erosion. Some of them are simply weathered Roman roads.