| Location | Osaka Pref. |
|---|---|
| Shape | Keyhole-shaped mound |
| Mound length | 173 m |
| Period | Mid–late 5th c. |
173m mound in Misaki Town, managed by the IHA.
IHA-designated mausoleum (Udonohaka, for Prince Inishiki, son of Emperor Suinin); excavation prohibited. From exterior survey, the three-tiered mound form is confirmed; traces of stone paving (fukiishi) and haniwa rows have been reported. The basic structure of the 173m keyhole mound with surrounding moat is established from surface observation. Internal burial chamber and grave goods unknown. Forms the Tannoha kofun group with the nearby Seiryo Kofun (Tannoha reference site, 210m). A chronological gap exists between the archaeological date (mid–late 5th century) and the chronicle period of the IHA's attributed prince (3rd–4th century).
Situated on a hill overlooking Osaka Bay near the ancient Awajima port, alongside the nearby Seiryo Kofun (210m). Together they are thought to mark the tombs of local chiefs who controlled the coastal routes. The IHA designates this as the tomb of Prince Inishiki (son of Emperor Suinin).