La Brea Tar Pits are a group of tar pits around which Hancock Park was formed in urban Los Angeles. Natural asphalt (also called asphaltum, bitumen, pitch, or tar—brea in Spanish) has seeped up from the ground in this area for tens of thousands of years. The tar is often covered with dust, leaves, or water. Over many centuries, the tar preserved the bones of trapped animals. 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.