The word “chise” in the Ainu means “a house,” which could be seen in the Ainu Kotan (village). It was normally built in Yosemune-zukuri style（a square or rectangular building.）The building materials of an Ainu house varied according to geographical and climatic conditions. Bamboo leaves, wild grasses, thatch, reed grass and tree bark were used for roofs and walls, which were tied with grapevine or tree bark. The wood of chestnut, Japanese Judas tree and Amur maackia were used for supporting pillars, which were directly set up without foundation stones. A chise has three windows; the one in the back is a rorun-puyar (god’s window), through which the gods entered, the one on the right is for letting in light, and the one near the entrance is for cooking ventilation. The orientation of the houses in a kotan (village) is identical; in most of the cases, a house is oriented from east to west with the god’s window facing the east. A chise was 33 to 99 square meters in area. It was a warm and comfortable home of the Ainu in the old days.