Dating Map (IMAGE) University of Helsinki Caption Cereal grains radiocarbon-dated to the prehistoric period. Cereal grains dated to the Pitted Ware period (3300-2300 BCE), the Bronze Age (1500-500 BCE) and the Iron Age (500 BCE-1200 CE) and their discovery sites. Credit Santeri Vanhanen 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.