At ten-and-a-half-feet tall, the Pentaceratops skull at the Sam Noble Museum of Natural History has the record for the world’s largest land vertebrate skull.

The enormous fossil with its towering frill is attached to a fully articulated Pentaceratops body, and it’s estimated that the living creature weighed around 13,000 pounds. The Pentaceratops is similar in shape to the better-known Triceratops, although with a couple more horns jutting from its head. The five-horned dinosaur skull was discovered in New Mexico in 1941.

However, due to the onset of World War II and the loss of scientific funding, the massive cranium was left in its rock matrix in crates underneath the football stadium at the University of Oklahoma. (Sadly the University of Oklahoma mascot is not a Pentaceratops). In 1995, paleontologist D.E. Savage, who helped as a student on the original expedition, came to work on the museum’s new dinosaur exhibits and rediscovered the huge skull. The Pentaceratops skull is 15% larger than the previous record holder: a Torosaurus latus skull at Yale University’s Peabody Museum.

In 2010, Yale paleontologist Nicholas Longrich released a study that suggested the Sam Noble’s Pentaceratops may in fact be a new species of dinosaur: a Titanoceratops. This is due to 22 features of the dinosaur that are different in this specimen from the smaller Pentaceratops that have been found.

The Sam Noble Museum of Natural History is located on the campus of the University of Oklahoma. It also holds the world’s largest Apatosaurus and Saurophaganax maximus dinosaurs and the “Cooper Skull,” the oldest painted object found in North America.