When you think of the tallest dinosaur, it’s very likely you think of either the Tyrannosaurus Rex, Apatosaurus (previously called the Brontosaurus), or the Brachiosaurus. You would be wrong on all accounts. The mighty T-Rex topped out at about 20 feet tall, the Apatosaurus was about 30 feet tall, and the Brachiosaurus got up to about 50 feet tall. Meanwhile, the tallest dinosaur it about 59 feet. This honor of the tallest dinosaur belongs to the Sauroposeidon.

Sauroposeidon is said to be named after the Greek god Poseidon and its name roughly translates to “lizard earthquake god.” That’s a pretty awesome name. The fossils of this giant have been found in Oklahoma, Wyoming, and Texas with paleontologists believing that this dinosaur lived along the shores of the Gulf of Mexico. In fact, the very first Sauroposeidon fossils were found in Oklahoma by the Texas border and were so large that people thought they were tree trunks. It wasn’t until 1999 (5 years later) that they realized what the vertebrae fossils were and have since been dated back by about 110 million years ago. This dating puts it between the Aptian and Albian epochs in the Early Cretaceous Period.

The Sauroposeidon belongs to the clade Sauropoda, suborder Sauropodomorpha, order Saurischia, clade Dinosauria, phylum Chordata, and kingdom Animalia.