Como Bluff is the famous Wyoming fossil site that yielded many Jurassic dinosaur bones. The long ridge lies between Rock River and Medicine Bow and exposes rocks from the Sundance, Morrison, and Cloverly formations. The Morrison Formation, deposited during the Late Jurassic, is especially rich in dinosaur fossils.
Como Bluff became central to the late-19th-century “dinosaur rush.” Paleontologists working there recovered remains of animals including Allosaurus, Apatosaurus, Camarasaurus, Camptosaurus, and Stegosaurus. The site helped establish that Jurassic ecosystems contained a remarkable variety of large plant-eating and meat-eating dinosaurs, rather than just a few famous types.
The location is also important beyond dinosaurs. Its quarries produced fossil mammals, turtles, crocodilians, and fish, including discoveries that greatly expanded knowledge of early Jurassic mammals. Como Bluff is sometimes confused with Dinosaur National Monument, another major fossil locality, but that monument is in Utah and Colorado and is best known for its exposed bone-bearing quarry wall. Hell Creek is also a famous fossil formation, but it is primarily associated with Late Cretaceous dinosaurs such as Tyrannosaurus rex.