廻原１号墳は､畿内地域の大王や官人層が埋葬方法として採用した｢横口式石槨｣をもつ､出雲地域で唯一の古墳として位置づけられてきた｡しかしながら､墳丘の測量調査や埋葬施設の実測図作成はこれまでに幾度かおこなわれているものの､発掘調査が実施されたことはなく､古墳の実態は依然として不明であった｡島根大学法文学部考古学研究室では､2010・2011年度に廻原１号墳の発掘調査を実施し､上記の課題解決を試みた｡調査の結果､古墳の墳丘形態や構造の一端を把握するとともに､埋葬施設についても新たな所見を得た｡墳丘や埋葬施設には､出雲地域の古墳に特徴的にみとめられる要素があり､畿内地域の例とは異にする点が目立つ｡その背景には出雲地域の主体性がうかがわれ､墳墓築造に在地の裁量がある程度許容されるような､畿内地域との緩やかな関係性を想定しうる｡古代出雲の実像に迫る重要な成果であり､今後さらなる検討を進めれば､出雲国の成立事情をさまざまな位相で論ずる材料を提示できるだろう｡

Megurihara No.1 ancient tomb has been estimated in Izumo district that it is the only grave of the corridor-style stone compartment protecting a coffin that the king and government official of Kinai district adopted. However, excavation investigation was not conducted although survey investigation was conducted. Therefore, the detailed information on an ancient tomb did not exist. Then, we conducted excavation investigation of the ancient tomb in the 2010 and 2011 fiscal year. As a result, the form and structure of the ancient tomb were clarified and a part of structure of the main burial facility became clear. It can be estimated that the feature of an ancient tomb differs from the example of Kinai district While it is common to the example of Izumo district. That is, there is originality of the Izumo district in how to make an ancient tomb grave, and it is thought that the relationship of Izumo district and an Kinai district was flexible. The result is the importance for which the real image of ancient Izumo is clarified. From now on, if it further inquiries, we will be able to be discussed on the process in which a settlement of the area indicated from many points of view.