El Malpais National Monument (IMAGE) University of South Florida Caption Archeological site next to the cave where it is believed that Ancestral Puebloans left circle-shaped stones while out hunting or used for ceremonial purposes. Credit University of South Florida Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.