The Dinosaur Park in Prince George's County, Maryland, is located on a hillside where erosion exposes clays deposited in an extensive wetland during the Early Cretaceous. Frequent fossil finds include lignite, or brown coal, formed from conifer trees that lived in the wetland, and fossilized cones. Sharp-eyed (and lucky) visitors may also discover dinosaur bones and teeth.
Important fossils discovered at the park are transferred to the Department of Paleobiology at the Smithsonian Institution where they are kept available for scientific research. Some of them are on also display in the 'Dinosaurs in Our Backyard' exhibit.