Edmontosaurus ("Edmonton's Lizard"), as well as previously called Anatotitan ("Giant Duck"), was a large hadrosaur dinosaur, a member of the ornithischian dinosaurs and the most common groups of dinosaurs in the Late Cretaceous, from the Cretaceous. It was one of the last non-avian dinosaurs on Earth before the mass extinction event.
Edmontosaurus lived in western North America during the Late Cretaceous period from 70-65 million years ago. It was among the biggest herbivore of its time.
Edmontosaurus was a very large dinosaur with a massive 23 foot tail, arguably the largest members of the hadrosaur family. They measured over 40 feet (12.3 meters) long, stood 13 feet tall at the hips, and weighed 4-6 tons, the size of a railroad box car.
These duck-billed dinosaurs lived in small groups to large herds. When feeding, huge batteries of chewing teeth made short work of the vegetation they ate. Like the Iguanodon dinosaurs about some 20 million years earlier, Edmontosaurus walked on four legs but ran on two.