Keyhole mound 140m in Ichinomoto-cho, Tenri City. Nationally renowned as the findspot of the "Chuhe"-inscribed iron sword (National Treasure). The sword bearing the Later Han dynasty era name Chuhe (184–189 CE) is among the most important artifacts documenting contact between early Japan and Later Han China. Protected as a National Historic Site; exterior viewing accessible. Tenri City is a treasure trove of Japanese archaeology; combined visits with Isonokami Shrine and the Tenri University Sankoin Museum are strongly recommended.
Finds & research
Finds: Chuhe-inscribed iron sword (National Treasure), painted deity-and-beast mirrors, triangular-rimmed mirrors, iron objects, beads. Vertical-shaft stone chamber confirmed.
Two views on the occupant
Archaeological view
Keyhole mound 130m; rear circle 70m diameter, front section 72m wide. Three-tier construction with moat. Dated late 4th century. The mound is celebrated for the recovery of a "Chuhe"-inscribed iron sword (National Treasure) from the vertical-shaft stone chamber in the rear circle. "Chuhe" was a Later Han dynasty era name (184–189 CE), making this a key indicator of diplomatic exchange with Han China. Other finds: painted deity-and-beast mirrors, triangular-rimmed mirrors, iron objects, beads. Occupant unknown; considered an important chieftain of the early Yamato state.
Imperial Household Agency view
Not managed by the IHA. National Historic Site (1976). Managed by the Tenri City Board of Education. No IHA designation; multiple excavations conducted. Recovered artifacts include items designated National Treasures.
Field notes
The "Chuhe"-inscribed iron sword is held at the Tokyo National Museum. Despite the name "Todaijiyama," this mound has no connection to Todaiji Temple. Tenri City is rich in archaeological sites: Isonokami Shrine, Kurozuka Kofun, Yamanobe-no-Michi. Nearest access: ~15 min. by bus from Kintetsu "Tenri" Station.