Duck-billed dinosaurs varied considerably in the shape of their skulls.

Corythosaurus was characterized by a large bony crest composed of the nasal and premaxillary bones. This crest extended up over the head and was shaped like an ancient warrior's helmet from Corinth (Greece). The arms were short, but trackways show that duck-billed dinosaurs usually walked on all fours.

The diorama in Dinosaur Hall created by Ottmar von Fuehrer and Carl Beato in the 1950s depicts that era's interpretation of the life habitat of Corythosaurus. More recent research shows that environments in western North America during Late Cretaceous times were more similar to those in the southern and southeastern United States today.

The cross-sectional model of a restored Corythosaurus skull shows the structure of the air passages. The skull mounted on the skeleton shows the premaxillae, the bones normally forming only the tip of the upper jaws, extending upward to form the front part of the crest of the skull. The nasal bones are pushed up, forming the top and back of the crest. The cross-section shows air passages extending up into the crest to form an air chamber, which may have been used for making sounds, perhaps to communicate with other members of the herd.