The Minato City area, from the middle of the mid period, that is from around 100 BCE, saw the introduction of genuine agriculture including rice cultivation, and the start of the Yayoi Period. We think that people at this time built their tombs at Mitadai, and lived in the surrounding area. It is also possible there were people who made their tombs on the hills of Shiba. Activity by people of the Yayoi Period declined for a time in the first half of the late period, but revived in the second half of the late period, and moving into the following Kofun Period.