These dozens of footprints are dated to 150 million years ago. They correspond to the movement of sauropods, diplodocus or brontosaurs, i.e. large herbivores weighing around 20 tonnes. The weight of the animals has left notable marks in the mud, such as bulges 35-40 centimetres in diameter. Sometimes you can even see the fingers! These dinosaurs were plantigrades at the back and digitigrades at the front.
Two parallel tracks run up the platform for about 40 metres. In search of food, there must have been five or six of them, or perhaps more.
The footsteps left by these giants make us understand that the region was not entirely under water, as was long believed. We understand that there were shallows as well as land; islands large enough to support entire herds.
But how did these traces come to us? Sediments covered them and sank them deep into the earth; then plate tectonics shook the layers, which folded, fractured and rose to the surface. The erosion of glaciers then cleared them.