Edmontosaurus was a large herbivorous dinosaur that lived during the Late Cretaceous period. Its name means ‘Edmonton lizard; after the location of its discovery (Edmonton, Alberta, Canada). One of the last non-avian dinosaurs to ever exist, Edmontosaurus coexisted with dinosaurs like Triceratops, Tyrannosaurus, Ankylosaurus, and Pachycephalosaurus before their notorious demise.

Edmontosaurus measured up to 12 metres (39 ft) in length and weighed around 5.6 metric tons in body mass, although some individuals would have been much larger. Edmontosaurus was part of the Hadrosauridae, or duckbill family of dinosaurs, who are known for their distinctive teeth with each side of the jaw having three rows of sixty or more perfectly interlocking teeth.

Widely distributed across western North America, ranging from Colorado to the northern slopes of Alaska, the distribution of Edmontosaurus fossils suggests that it preferred coasts and coastal plains. 

In July 2024, an adult Edmontosaurus skull was sold at Sotheby’s Natural History sale for $42,000 - exceeding its lower estimate.