Located one-eighth mile west is an ancient asphaltum seepage where hundreds of Pleistocene Age birds, insects, and animals were trapped fifteen thousand to fifty thousand years ago. Skeletal remains found in the pit include giant condors, giant long-horned bison, Harlan's ground sloth, Western camel, dire wolf, and saber-toothed cats, among the extinct animals that once lived in Kern County. The site was first explored in 1928 by the University of California, again in 1933 by the Smithsonian Institute, which employed 200 workers from the Civilian Works Administration, and underwent a final excavation in 1949 by the Los Angeles and Kern County Museums.