Riker Hill Fossil Site is a 16acre paleontological site in Roseland in Essex County, New Jersey, United States, located at the south western side of the borough at the border between Roseland and Livingston. It is one of the major sites in United States where a large number of dinosaur tracks are preserved. It was declared a National Natural Landmark in June 1971.HistoryOriginally, the site was part of a 55acre stone quarry owned by the Kidde company called Roseland Quarry. In 1968, there was a discovery of dinosaur tracks on the quarry. With the news, a 14-year-old, Paul E. Olsen who lived in Livingston, and his friend Tony Lessa started visiting the quarry to study them. Over a period of a few years, they uncovered more than one thousand dinosaur, animal and insect tracks from the Late Triassic and Early Jurassic period.When the fate of the quarry site became uncertain, the teens came up with a plan to prevent the site from being developed. They made a cast from a footprint of Eubrontes Giganteus and sent that to President Richard Nixon to get support. Eventually, the quarry was split. The most productive portion was preserved and donated to the Essex County Park Commission and named after Walter Kidde. The rest of the quarry was later developed into Nob Hill apartments. In June 1971, the preserved site was registered as a National Natural Landmark.