Onions have layers, ogres have layers...The Badlands also have layers! Each layer of the Badlands corresponds with different moments in geologic time. They start with the oldest layer at the bottom, then move upwards in space and time towards the youngest layer, which sits at the top of the formations. These layers also help paleontologists determine the relative age of the fossils found within the park. NPS Photo #FindYourPark #Geology #Fossils