The change from a ranked chiefdom society to a state society was one of the most important developments during this time. Initially, the Magyars retained a semi-nomadic lifestyle, practising transhumance: they would migrate along a river between winter and summer pastures, finding water for their livestock. According to Györffy's theory derived from placenames, Árpád's winter quarters -clearly after his occupation of Pannonia in 900- were possibly in 'Árpádváros' (Árpád's town), now a district of Pécs, and his summer quarters -as confirmed by Anonymus- were on Csepel Island. Later, his new summer quarters were in Csallóköz according to this theory, however the exact location of the early center of the state is disputed. According to Gyula Kristó the center was located between the Danube and Tisza rivers, but the archaeological findings imply a location in the region of the Upper Tisza.