People usually consider Colorado the Wild West, known for its gunslingers, cowboys, and pioneers. But it also has a rich paleontological and geological history. In fact, it is one of the best states in the American West to explore dinosaur fossils and footprints. It even has a whole town called Dinosaur! The state dinosaur is the Stegosaurus.

Various fossils suggest around 300 million years ago, a shallow sea covered the entire state. The sea started receding 100 million years ago, allowing vegetation and animals to thrive. That was when the first dinosaurs appeared in the wet and humid environments.

The Permian era, 47 million years ago, saw the sea disappearing. Sand dunes covered the land providing optimum conditions for fossils to form. The following Triassic period again saw the ground covered by a shallow sea, facilitating the growth of rainforests. That was when conditions became suitable for the larger dinosaurs to survive. 

List of Dinosaurs That Lived in Colorado

• Allosaurus
• Apatosaurus
• Diplodocus
• Haplocanthosaurus
• Ornithomimus
• Stegosaurus
• Triceratops
• Tyrannosaurus rex

Places Where the Fossils are Preserved

Plenty of paleontological sites are scattered throughout the state, making it an excellent spot for dinosaur enthusiasts. The fossils uncovered here are in the form of impressions, footprints, and partial remains.

The Dinosaur Ridge has the fossils and footprints of Stegosaurus and Apatosaurus. Thousands of dinosaur fossils have been discovered at the Dinosaur National Monument since the early 1900s. The Picketwire Canyonlands has the largest collection of fossilized dinosaur tracks in the US.