Kushiyama Kofun is an ancient burial mound located in Yanagimoto-cho, Tenri City, Nara Prefecture. It was constructed during the latter half of the early Kofun period, when powerful ruling families built monumental tombs to demonstrate their authority. The tumulus belongs to the Yanagimoto Kofun Group and stands on elevated ground beside Andonyama Kofun, traditionally identified as the tomb of Emperor Sujin.
Kushiyama Kofun is particularly notable for its unusual shape, known as a double-ended circular tumulus or ryōhō-chūen-fun in Japanese. Unlike the more familiar keyhole-shaped burial mounds, it features a central circular section with projecting sections on both the east and west sides. Its distinctive design, elaborate burial remains, and numerous grave goods make it an important site for understanding the funerary practices, engineering skills, and spiritual beliefs of ancient Japan.
The defining feature of Kushiyama Kofun is its rare layout. A large central circular mound is flanked by a forward-projecting section to the west and a rear section to the east. This configuration differs from the standard keyhole-shaped tumuli found throughout Japan and provides valuable evidence of the variety of burial mound designs used during the early Kofun period.
Comparable examples include the Tatetsuki Archaeological Site in Okayama Prefecture and Nekozuka Kofun, part of the Ishikioyama Kofun Group in Takamatsu, Kagawa Prefecture. These sites illustrate the existence of distinctive regional traditions in monumental tomb construction. Tatetsuki dates to the end of the Yayoi period, approximately a century earlier than Kushiyama Kofun and similar tumuli built during the latter half of the early Kofun period.
The mound measures approximately 152 meters in total length, making it a substantial monument. Its central circular section has a diameter of about 90 meters, while the western projecting section measures approximately 60 meters in length and the eastern section about 25 meters.
The tops of the central circular section and the western projection are relatively flat. Small white stones, approximately 3–4 centimeters in diameter, are believed to have been spread around the burial facility. These pale stones would have created a distinctive surface around the area associated with the deceased.
The central circular section and the eastern rear section were constructed in three tiers, while the western projection had two tiers. Flat, slab-like stones measuring approximately 30 centimeters are thought to have covered the mound’s surface as protective facing stones. This construction would have helped define the mound’s monumental form while protecting its earthen structure.
Although no visible moat currently surrounds Kushiyama Kofun, the surrounding landscape includes areas now used as rice paddies that are believed to preserve the outline of an ancient surrounding moat. The estimated moat area extends approximately 190 meters from east to west and 165 meters from north to south. Along the sides of the western projection, the width is estimated at about 56 meters.
These remains offer clues to the original appearance of the burial mound and its relationship with the surrounding landscape. Even where the original structures have disappeared, the contours of agricultural land can help archaeologists reconstruct the scale of ancient monuments.
Archaeological investigations have also revealed evidence of sophisticated drainage arrangements. A pit measuring approximately 5 meters long and 3.4 meters wide was identified at the site. This feature provides insight into the engineering knowledge employed in the construction of large burial mounds during the Kofun period.
Such remains demonstrate that these monuments were not simply enormous piles of earth. Their construction required careful planning and an understanding of ground conditions, water management, and the stability of large structures.
In 1943, during the Pacific War, an archaeological investigation was carried out in connection with plans to construct an airfield. The excavation uncovered a stone-lined vertical burial chamber at the summit of the central circular section. The chamber measured approximately 7.1 meters long and 1.4 meters wide.
Parts of a stone sarcophagus assembled from multiple pieces remained inside the chamber. Known as a nagamochigata sekkan, this long, chest-shaped sarcophagus is associated with the burial practices of high-status individuals in ancient Japan. Its presence provides important evidence of the social standing and funerary traditions connected with Kushiyama Kofun.
No burial facility has been confirmed in the eastern section of the mound. Instead, archaeologists identified a structure thought to have served a ceremonial or ritual purpose.
Evidence suggests that after burial ceremonies, everyday objects and clay ornaments, including magatama comma-shaped beads and cylindrical kudatama beads, were deliberately broken. The fragments were then thrown into a pit together with stones. This unusual practice offers a glimpse into the ritual customs and beliefs surrounding death in the Kofun period.
A large collection of grave goods was recovered from the eastern section of Kushiyama Kofun. Particularly notable are ornaments made from jasper, including stone bracelets and bracelet-shaped objects known as ishikushiro, sharinseki, and kuwagataishi.
The excavated collection included 107 ishikushiro ornaments, 105 sharinseki ornaments, and 23 kuwagataishi ornaments. These objects are important for understanding the decorative arts, burial customs, and status symbols of the period. Clay imitations of the stone ornaments were also discovered, together with cylindrical beads and iron objects such as swords, small knives, and axes.
Other finds included stone objects shaped like memorial tablets, possibly representing stylized human figures, as well as pottery such as raised-stem vessels and jars. Collectively, these artifacts offer clues to how people in ancient Japan understood death, spiritual power, and the relationship between the living and the dead.
A layer of accumulated white stones in the eastern section yielded a clay object shaped like a kuwagataishi ornament and decorated with a distinctive chokkōmon pattern, formed from intersecting straight and curved lines.
This artifact is valuable for its combination of decorative design and possible ritual significance. It also helps researchers investigate the artistic traditions and symbolic forms that developed during the Kofun period.
Kushiyama Kofun is surrounded by other important archaeological sites and cultural landmarks that illuminate the history of ancient Japan. Visiting several of them together provides a broader understanding of early rulers, burial traditions, and the development of political authority in the Nara Basin.
Andonyama Kofun (Emperor Sujin’s Mausoleum): Located immediately beside Kushiyama Kofun, this enormous burial mound is traditionally associated with Emperor Sujin, one of Japan’s early legendary emperors.
Shibutanimukoyama Kofun (Emperor Keikō’s Mausoleum): Another monumental tomb traditionally linked to an early emperor, offering further insight into the region’s concentration of ancient burial sites.
Nishitonozuka Kofun (Tomb of Princess Tashiraka): This ancient mound is traditionally identified as the burial place of Princess Tashiraka, a figure associated with the imperial lineage.
Kuozuka Kofun and the Tenri City Kurozuka Kofun Museum: The burial mound and its museum provide additional opportunities to explore archaeological discoveries and the funerary culture of the Kofun period.
Chōgaku-ji Temple: A historic temple in the surrounding area, offering a different perspective on the region’s long religious and cultural heritage.
Kushiyama Kofun is far more than an impressive earthen mound. Its rare double-ended design, sophisticated construction, stone burial chamber, ritual remains, and rich collection of grave goods reveal the technical abilities and spiritual traditions of the people who lived in ancient Japan.
Situated among the historic tumuli of Tenri, the site is an especially rewarding destination for travelers interested in archaeology, early Japanese history, and the origins of the country’s ancient ruling classes. Exploring Kushiyama Kofun alongside nearby burial mounds and temples helps bring the distant world of the Kofun period into clearer focus.