Tawayama and Jigode Sites

A Settlement with No Houses Inside Its Moats

The Tawayama and Jigode Sites (田和山・神後田遺跡, Tawayama Jigode Iseki) are the remains of a Yayoi settlement of the late Early to late Middle period across Noshiro-cho, Hamanogi-cho and Nogifukutomi-cho in Matsue City, Shimane Prefecture, designated a Historic Site on 13 August 2001. The Jigode site to the north was added on 15 March 2022, giving the present name.

The Agency for Cultural Affairs states the site's peculiarity in a single sentence: excavation showed a settlement with triple moats of a form never seen before, in that the moats encircle the hilltop but the dwellings lie outside them. A Yayoi moated settlement normally keeps its houses and storage pits within the moat. At Tawayama, for the whole life of the settlement, no one lived inside.

The site came to light between 1997 and 2000 during excavation by the Matsue City board of education ahead of construction of a municipal hospital. Once the unprecedented structure was recognised the building plan was changed and the site preserved as found. It occupies an isolated hill rising 36 metres above its surroundings, looking north over Lake Shinji.

Triple Moats: From One Ring to Three, Then Abandoned

The moats surrounded the summit at the northern end of a hill running north to south. In the late Early Yayoi there was a single moat, not closed, with three gaps left undug. In the Middle Yayoi it became triple.

The area enclosed by the innermost moat is 2,250 square metres. The moats reach 7 metres wide and 1.8 metres deep at their largest. Traces of earthen banks survive in places between the moats and outside the outermost. For a Yayoi settlement, cutting three rings of ditch and bank around a hilltop was a large undertaking.

For all that work, no one settled inside. In the late Middle Yayoi the moats were abandoned.

Post Holes on the Summit, Houses Outside

Many post holes were found on the summit. In the Middle Yayoi a fence is thought to have enclosed the whole top, with a structure on posts, probably a raised building, at its centre; a similar arrangement is supposed for the late Early period too. Buildings on five and on nine posts have been identified, and a hall for rites has been suggested.

Eleven pit dwellings of the Middle Yayoi were found, all outside the moats, ten of them clustered on the north side. Around the houses were twelve terraced features cut into the slope to make level ground, also Middle Yayoi.

Fence and building on the summit, houses outside the moats. The arrangement shows that the enclosed ground was set apart for something other than living. A ritual precinct, a hill fort and a store for bronze ritual objects have all been proposed, and the question is open.

Finds: More Than 3,000 Stones

The finds include pottery and stone tools of various kinds. What the Agency singles out are the more than 3,000 natural stones recovered from the moats, which may have served as throwing missiles. Many chipped stone arrowheads came out, along with polished stone swords.

The citation frames this against the received view. Yayoi moated settlements have been understood as defensive or military in character, or as regional centres. At Tawayama weapons are present, but the dwellings spread outside the moats, so the structure differs from a moated settlement with ordinary defensive purpose.

A slate inkstone possibly made in the Lelang commandery was also found. Whether it arrived by way of northern Kyushu or directly from the Korean peninsula is unknown, but it is taken as evidence of contact with the wider East Asian world. The most important finds were designated Shimane prefectural cultural properties in 2019.

The Agency concludes that although the settlement had moats, it appears to have been of a different character from any moated settlement found before, and that its scholarly value for understanding settlement structure and the nature of moats is extremely high.

Visiting: A Historic Site Park

The site is laid out as a park, free to enter and open every day. It is an outdoor site, so avoid entering after dark. Free parking is provided.

On the summit the positions of the fence and the posts are marked with upright indicators, showing where the five-post and nine-post buildings stood. In the moat area the three rings and the traces of bank can be walked. From the top the view takes in Lake Shinji, the Shimane peninsula and the city of Matsue.

The Jigode site lies about 500 metres to the north. Since the addition made the two a single Historic Site, walking both gives a sense of what the designation covers.

From Nogi Station on the JR San'in Main Line it is about 20 minutes by bus or on foot, or about 10 minutes by car from JR Matsue Station. Enquiries go to the Matsue City buried cultural properties division on 0852-55-5284.