Guess what! There used to be a dinosaur, millions of years ago, named Parasaurolophus.
This wasn’t any ordinary dinosaur, it was as long as 4 cars placed bumper to bumper, and it walked on two feet!
The Parasaurolophus is best-known for the long, curved crest on its head, almost like a trumpet sticking out backwards from its skull.
Scientists believe that this crest might have been used like a trumpet, to make loud noises, attract mates, or warn others of danger.
The Parasaurolophus lived in North America, particularly around what is now Utah and New Mexico, about 76 million years ago.
This was during a period known as the Late Cretaceous period, the tail-end of the age of dinosaurs.
These big lizards were plant-eaters, using their sharp teeth to munch on leaves and tree branches.
Despite being such a large creature, it is believed to have been gentle and social, moving in herds for protection.
So if you were a kid during the time of the Parasaurolophus, you might have seen them wandering around in big, noisy groups, looking a lot like how we see cows on a farm today!