La Brea Tar Pits comprise an active paleontological research site in urban Los Angeles. Hancock Park was formed around a group of tar pits where natural asphalt has seeped up from the ground for tens of thousands of years. Over many centuries, the bones of trapped animals have been preserved. The George C. Page Museum is dedicated to researching the tar pits and displaying specimens from the animals that died there. "La Brea Tar Pits" is a registered National Natural Landmark.