Scientists have discovered Ningxia's largest group of sauropod dinosaur footprint fossils in the Liupan Mountains. Over 241 well-preserved footprints dating back 110 million years were discovered on a cliff. These tracks were left by giant dinosaurs measuring 15 to 22 meters long. Fossil records show the path the dinosaurs took and even the speed at which they walked. This precious discovery provides key evidence for the study of prehistoric creatures and the ancient ecosystem of northwest China.