Aizu Otsukayama Kofun

A keyhole-shaped tumulus located in Otsukayama, Ikki-cho, Aizuwakamatsu City, Fukushima Prefecture. It is also called Otsukayama Kofun. It is a nationally designated historic site. It was investigated by the Aizuwakamatsu History Compilation Committee in 1964 (Showa 39). It is the oldest keyhole-shaped tumulus in the Tohoku region, estimated to have been built around the end of the 4th century, and is a handle-mirror-style keyhole-shaped tumulus measuring 90 meters in total length. The circular rear part is about 45 meters in diameter and 6 meters high. The circular rear part has a moat cut into the hill about 20 meters wide. It was built facing north on the top of an independent hill in the southeastern part of the Aizu Basin. The internal structure shows traces of two split bamboo-shaped wooden coffins at right angles to the main axis in the circular rear part, and the southern coffin is about 8.7 meters long and made of clay on both ends. The excavated items are nationally designated Important Cultural Properties. In the southern coffin, a three-god and two-beast mirror with an imitation triangular-rimmed arabesque pattern, a small four-beast mirror, a trefoil-patterned ring-headed sword, a bronze arrowhead, a rectangular iron axe, jewels, and the remains of a quiver with a straight-arc pattern were excavated. In the northern coffin, a jasper spindle wheel and a small twisted pattern mirror were also unearthed. A similar triangular-rimmed god and beast mirror can be found in the Tsuruyama Maruyama burial mound in Okayama Prefecture.

[Genzo Ito]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

福島県会津若松市一箕(いっき)町大塚山にある前方後円墳。大塚山古墳ともいう。国指定史跡。1964年（昭和39）会津若松史編纂(へんさん)委員会により調査された。4世紀末ごろ築造と推定される東北地方最古の前方後円墳であり、全長90メートルを計る柄鏡(えかがみ)式前方後円墳である。後円部径約45メートル、高さ約6メートル。後円部には幅約20メートルの丘陵切断の堀をもつ。会津盆地の南東部独立丘頂部に、北向きに築造されている。内部構造は、後円部に主軸直交の2本の割竹形木棺の痕跡(こんせき)があり、南棺は約8.7メートルの長さであり、両端粘土使用である。出土品は国指定重要文化財。南棺では仿製三角縁唐草文(ぼうせいさんかくぶちからくさもん)帯三神二獣鏡、小形四獣鏡、三葉文環頭大刀(かんとうのたち)、銅鏃(どうぞく)、短冊形鉄斧(てっぷ)、玉(たま)類などのほか、直弧文(ちょっこもん)のある靫(ゆき)遺残が出土。北棺も碧玉(へきぎょく)製紡錘車(ぼうすいしゃ)、小形捩文(ねじもん)鏡などが出た。三角縁神獣鏡は岡山県鶴山丸山古墳に同笵(どうはん)がある。

［伊藤玄三］

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例