The Tokachi Horokayanto Pit Dwelling Group is a major dwelling settlement of indigenous people built spanning approximately 2km north-south on the Bansei coastal terrace, 15m in elevation, facing the Pacific Ocean, and over 130 locations are also distributed in the surrounding area. As for artifacts, Satsumon-style pottery is primary, and in addition to a small number of obsidian stone tools excavated accompanying the pottery, stone weights believed to be for fishing, slightly processed natural stones, a large number of small stones believed to have been used as weights for mat weaving, corroded iron fragments believed to be fragments of metal implements, and animal skeletons have been excavated.

The feature of this site is that both pottery and stone tools are few in number and metal implements have been excavated, and the fact that Okhotsk-style pottery was also excavated is noted. Probably, in the Satsumon culture period, the use of stone tools had already declined, and it is believed that many metal implements and wooden implements, etc., were being used. These historic sites were registered as Hokkaido Designated Historic Sites on July 7, Showa 41.