The Dinosaur Ridge in Morrison, in the state of Colorado, is one of the world’s most famous dinosaur sites. Discovered in 1877 by Arthur Lakes, it was here where some of the best-known dinosaurs, including Apatosaurus, Diplodocus, Stegosaurus, and Allosaurus, were first identified. Bones from Stegosaurus and Apatosaurus are still exposed in the rocks today, and can be felt and touched. Another attraction is a stony incline, exposed in 1937, with hundreds of dinosaur footprints fossilized in the rock. These tracks were made by Iguanodon-like herbivores and ostrich-sized carnivores about 100 million years ago, when the dinosaurs were migrating north and south along the shore of the ancient inland sea.