Local paleontology in Washington, D.C., is known primarily for two serendipitously discovered dinosaur fossils. The first was a vertebra from a carnivorous dinosaur nicknamed "Capitalsaurus" that was related to Tyrannosaurus rex. "Capitalsaurus" is the official dinosaur of the District of Columbia; the place it was discovered was named Capitalsaurus Court in its honor and it even has its own local holiday. The second major fossil find was a thighbone from the long-necked sauropod Astrodon. The District of Columbia and Maryland are the only places where Early Cretaceous dinosaur remains are known to have been preserved east of the Mississippi River.[1]