This is a report on the three ruins that excavated in FY 1986. The Nosaka Hoteta ruins (Nasaka Hotashi) consists of a group of mining pillar buildings centered on the latter half of the 12th century and the first half of the 13th century, and a group of iron cabbages (tatami), shavings (bamboo shoots) The soil pit including the groundwork is surveyed and it can be seen as a race related to the smith. Yoshitoshita Sobara ruins (Yoshidomi Shimamoto Buraku Ikki) was investigated the group of warehousing excavated from the latter half of the 6th century to the beginning of the 7th century, and the earth in the late Jomon period. It is the first excavation investigation in the Munakata area as the ruins of the late Jomon period. Mitsukioka Kusaba ruins (Mitsuoka Kusaba Ikeki) found 24 soil mounds from the mounds of the ancient tomb and 2 pots for pediatric jar of the Yayoi era.