Saitobaru Burial Mounds (Saitobaru Kofungun)

Saitobaru Burial Mounds form the largest concentration of ancient tumuli in Japan, comprising more than 300 kofun (burial mounds) spread across a plateau in Saito City, Miyazaki Prefecture. Constructed between the late 3rd and 7th centuries CE during the Kofun period, the site preserves a mix of keyhole-shaped zenpokoenfun, round enfun, and square hofun mounds built for regional chieftains and their clans as Japan's early state structures took shape in southern Kyushu. Designated a Special Historic Site by the national government, Saitobaru is considered one of the most important archaeological landscapes for understanding the Hyuga region's role in early Japanese political formation, including its ties to the Kojiki and Nihon Shoki mythological narratives about the origins of the imperial line. Excavations at mounds such as Saitobaru No. 100 and No. 111 have recovered haniwa clay figures, bronze mirrors, iron weapons, and horse trappings, many of which are displayed at the adjoining Saitobaru Archaeological Museum. The park's grassy, tree-lined mounds are largely unexcavated and left in their natural state, allowing visitors to walk among the tumuli along marked trails rather than viewing reconstructed structures. Curatorially, the site is presented chronologically, with informational panels tracing the transition from Yayoi-period agricultural communities to the stratified Kofun-period society that produced the mounds. The largest mound, Josaibaru Kofun, stretches over 175 meters and remains one of the largest keyhole tombs in Kyushu. Restoration work has focused on erosion control and vegetation management rather than reconstruction, so the mounds retain their weathered, centuries-old profile. The surrounding Saitobaru Fudoki-no-Oka park also includes reconstructed Kofun-period pit dwellings and a small shrine, giving the site a layered historical character spanning from ancient burial practices to later Shinto worship.