The dinosaurs at the American Museum of Natural History NY

The dinosaur exhibits at the American Museum of Natural History are spread across several interconnected halls on the fourth floor, part of the David H. Koch Dinosaur Wing, together displaying roughly 600 fossil vertebrate specimens, including about 100 dinosaur specimens, some 85 percent of which are genuine fossils rather than casts. Visitors typically begin at the Miriam and Ira D. Wallach Orientation Center, home to the Titanosaur — a cast of the 122-foot-long sauropod Patagotitan mayorum, discovered in 2014, so enormous that its neck and head extend out toward the elevator banks since it's too long for the room itself. From there, a marked path leads through the Hall of Vertebrate Origins, tracing the evolution of backboned animals, and into the two dinosaur-specific halls: the Hall of Saurischian Dinosaurs, featuring the iconic mounts of Tyrannosaurus rex and Apatosaurus, along with predators like Allosaurus and Velociraptor; and the Hall of Ornithischian Dinosaurs, home to Triceratops, Stegosaurus, and duck-billed hadrosaurs such as Corythosaurus, including a rare "dinosaur mummy", a fossilized skin impression of a hadrosaur carcass. Rather than a simple chronological walk, the halls are organized to reflect evolutionary relationships, so a visitor moving through them essentially follows the branching structure of the dinosaur family tree, with a marked path denoting the evolutionary "trunk" and side alcoves exploring specific related groups. This design dates to a major renovation completed in stages during the mid-1990s: the Hall of Saurischian Dinosaurs and Hall of Ornithischian Dinosaurs both reopened in 1995, while the Hall of Vertebrate Origins followed in 1996. Beyond the two dinosaur halls, the fourth floor continues into the Hall of Primitive Mammals and the Paul and Irma Milstein Hall of Advanced Mammals, extending the evolutionary narrative into the age of mammals that followed the dinosaurs' extinction — together forming one continuous fossil-hall complex that AMNH describes as home to the largest dinosaur collection in the world.