The Beneski building combines the state-of-the-art with the prehistoric. Opened in 2006, it contains the faculty offices, labs and lecture halls of the College’s geology department. But its biggest draw is the Beneski Museum of Natural History, which is free and open to the public six days a week, and employs Amherst students as tour guides. Along with colorful minerals and meteorites displayed along its main corridor, the museum houses freestanding fossil skeletons of a mammoth, mastodon, dire wolf, saber-toothed cat, Irish elk and cave bear, as well as skulls of a Tyrannosaurus rex and a Triceratops. Its “newest” dinosaur skeleton is a Dryosaurus altus, donated in 2013. The Beneski also boasts the world’s largest collection of dinosaur tracks, amassed by Amherst College professor and president Edward Hitchcock in the mid-19th century, mostly from right here in the Connecticut River Valley. The 1,700 items publicly exhibited in the museum represent less than 1 percent of its total collection; the other 248,000 specimens are used primarily for coursework, original research and in-class demonstrations.