The Bronze Age refers to an era in which professional artisans made practical tools out of bronze alloys and developed into a complex hierarchical society. The Bronze Age begins around 1500 B.C., but lobe-shaped bronze swords were produced after around 1000 B.C. After about 300 B.C., when various bronze wares including thin bronze swords were produced and used, belonged to the early Iron Age. Bronze ware was mainly a symbol of authority or used for special ceremonies, and tools for daily life were ground stone tools, earthenware, and wooden products. Almost plain earthenware, fired in an open-air kiln, was used for food storage and cooking. As food was secured through agriculture, including rice farming, along with gathering, hunting, and fishing, the settled population increased and villages similar to today emerged. Through the Dolmen ruins built around the village, it is identified that a blood-related hierarchical society in which rulers appeared was formed.