| The Sannai-Maruyama site is a Jomon period site where continuous occupation took place for a long period of time (about 5500 ~ 4000 years ago).
From excavations carried out since 1992, remains of pit-dwellings, long houses, graves for adults and children, mounds of debris, remains of pillar-supported structures, storage pits, clay mining pits, refuse disposal pits and roads have been found revealing the characteristics of the settlement and the natural environment of the period.
In addition, a huge amount of Jomon pottery, stone implements, clay figurines, clay and stone ornaments, wooden objects such as digging sticks, woven bags and fabrics, and lacquered and bone items have been unearthed as well. Jade and obsidian were brought in from other areas.
Remains of cultivated edibles such as gourds, burdocks and beans have been excavated, and traces of chestnut cultivation have been revealed by DNA analysis, all helping to change the image of the Jomon culture.
The site was designated a Special National Historical
Site in November 2000.