ocated on a terrace at an elevation facing the Lake Ogawara, the Historic Site Futatsumori Site is an archaeological site of a settlement accompanied by large shell mounds in the early to middle Jomon Period (about 5,500-4,000 years ago). The lower layers contain the shells of saltwater shellfishes, such as clams and oyster, and the upper layers contain those of brackish shellfishes (Japanese basket clams and other shellfish). indicating that people developed their lives in the process of adapting to environmental changes. In addition, many bone and antler objects made from animal bones and horns have been found. Reflecting the high spirit and processing technology of that time, "deer horn comb", "green dragon knife shaped bone utensil made from whale bone", "deer horn pointed utensil", "wild boar's tooth pendant ornament", and "deer horn forked utensil" were designated as "Ken Juho" (treasure in prefecture level) and exhibited at the nearby the Futatsumori Shell Midden Museum.