本日紹介するのは・・・
茨城県行方市にある三昧塚（さんまいづか）古墳 （5）
Today I would like to introduce you to the Sammaizuka burial mound (5), located in the city of Missing City, Ibaraki Prefecture.
この古墳は全長82M、後円部の直径46.5M、高さ8Mの前方後円墳でそれほど大型ではない！
This Sammaizuka burial mound is not very large, with a length of 82 meters, a diameter of 46.5 meters at the back of the circle, and a height of 8 meters.
しかし車道から見た姿は巨大で美しい！
But it is huge and beautiful when seen from the road!
実はこの古墳、1955年に土砂として採取され、
失われる寸前だったのだ！
In fact, this tomb was almost lost in 1955 when it was extracted as earth and sand!
すでに半分近くが削られたころ、緊急発掘調査が行われ、
埋葬施設や豊富な副葬品が見つかった。
When almost half of the tomb had already been flattened, an emergency excavation was conducted and burial facilities and a wealth of burial accessories were found.
墳丘は基段の上に作られており、表面には円筒埴輪・形象埴輪（人物・鹿形・牛形・犬形）が配置され、墳丘周囲には周堀が巡らされていた。
The mound was built on top of a base terrace, with cylindrical haniwa (clay figurines) and figurative haniwa (figures, deer, cattle, and dogs) arranged on the surface, and a moat around the mound.
築造時期はは5世紀中頃～後半（古墳時代中期）らしい
It is said to have been built in the middle to late 5th century (mid-Kofun period).
埋葬施設は組合式箱式石棺で、特徴的なのは棺蓋！
he burial facility is a union-type box-shaped sarcophagus, and the distinctive feature is the coffin lid!
長さ2.3M・幅80CM・厚さ10CMあり、縄を掛ける突起があることから、のちの長持形石棺の流れをくむものらしい
It is 2.3 meters long, 80 cm wide, and 10 cm thick, and has a protrusion for hanging a rope, which suggests that it is in the style of the later long-handled sarcophagi.
石棺内からは、人骨のほか金銅製冠、変形四神四獣鏡 をはじめとする多数の副葬品が、また石棺付近の木製収納施設から武具・馬具類が出土
Inside the sarcophagus, in addition to human bones, a gilt-bronze crown, a mirror of the four gods and four beasts, and many other burial accessories were excavated, as well as armor and harness from the wooden storage facility near the sarcophagus.
これら出土物は国の重要文化財だ！
These artifacts are national important cultural properties!
被葬者は霞ヶ浦を治めていた有力首長と想定される
The funerary deceased is assumed to have been a powerful chief who ruled Kasumigaura.
三昧塚古墳はのちに復元され、出土品等は茨城県立歴史館（水戸市緑町）で 保管・展示されている。
The Sammaizuka burial mound was later reconstructed, and the excavated artifacts are stored and exhibited at the Ibaraki Prefectural Museum of History (Midori-cho, Mito City).
引用／現地説明看板及びウィキペディア（Wikipedia）
Reference: Local explanatory signs and Wikipedia (Japanese only)