Long ago, dinosaurs left footprints in the mud at the edge of an ancient ocean. Today, you can walk in their tracks in the bed of the Paluxy River in nearby Glen Rose. Begin your adventure at Dinosaur Valley by taking a selfie with the giant dinosaur models, Apatosaurus (70 feet) and Tyrannosaurus Rex (45 feet), which were once displayed at the 1964-65 New York World's Fair. Or you can simply follow the fossilized prints left by these ancient reptiles across the park's 1500 acres. Throughout Dinosaur Valley, hundreds of dinosaur footprints are waiting to be explored. There are a number of trails you can enjoy, from the Bird Track, where you can see the first sauropod trail discovered anywhere in the world, to the Ballroom Track, where dinosaur prints spread in all directions.