Orce is the location of the paleo-archaeological sites known as Barranco Leon, Venta Micena, and Fuentenueva 3, near the basin of an ancient lake where fossils have been preserved in sediment. Josep Gibert of the M. Crusafont Institute in Sabadell has led an excavation team there. He asserts that the sites have Oldowan-style stone tools dating between 1.5 and 1.8 million years ago. If the early estimates are supported, these would represent the oldest stone tool finds in Europe.  Other scholars prefer a more conservative date for the stone tools of 1.2 million years. Together with the hominid remains at the Atapuerca Mountains, the tools are evidence that human ancestors settled in western Europe much earlier than scholars had thought, perhaps by 400,000 years or more.