 These settlements scattered throughout the region evolved, some to become complex cultures with language and religion, stratified societies and priestly classes.Others collapsed and were forgotten until the recent discovery of its ruins and study of remains that repositioned them as key parts for the study and understanding of regional history.The most remote archaeological discovery is located in the archaeological area of San Miguel Ixtapan, atop of a pyramid basement, still unexplored; a mask and jade necklace were found alongside organic remains.