Sauropods were the largest of all dinosaurs. The largest sauropod tracks ever recorded were discovered in 2009, in the French mountain village of Plagne. Now, after further excavation and analysis, it has been announced that they are part of the longest sauropod trackway – or set of tracks – ever to be found.
Dating of the limestone in which the tracks are located indicate that they were made 150 million years ago, during the Early Tithonian Age of the Jurassic Period. The trackway extends over 155 meters (509 ft), and is made up of 110 individual tracks.
Based on biometric analysis of the prints, it has been determined that the animal which made them must have been at least 35 m long (115 ft), weighed 35 to 40 tonnes (39 to 44 US tons), had an average stride of 2.8 m (9.1 ft) and traveled at about 4 km/h (2.5 mph). The dinosaur has been assigned to the new ichnospecies (a taxon based on tracks and not on anatomical remains) of Brontopodus plagnensis.
The research was conducted by scientists from the Laboratoire de Géologie de Lyon, the Laboratoire Magmas et Volcans, and the Pterosaur Beach Museum. It is described in a paper recently published in the journal Geobios.