Kofun: Japan's Giant Keyhole Burial Mounds

Grassy hills shaped like keyholes, ringed by moats and once lined with clay figures, still rise quietly among modern streets.

Published October 18, 2026 at 11:32 PM JST | By Tokyo Paul

Quick answer: Kofun are the large earthen burial mounds built across Japan mainly between the third and seventh centuries, giving their name to the Kofun period. The best known have a keyhole shape and are surrounded by moats. The Mozu and Furuichi groups near Osaka, including the Daisen mound, were inscribed as a UNESCO World Heritage site in 2019.

What Kofun Are

Kofun (古墳) means old tomb. The word refers to the mounded graves of local rulers and elites constructed from about the third century to the seventh century. They range from small round mounds to enormous structures spanning hundreds of metres, and thousands survive across the country. The most distinctive form is the zenpo koen fun, a keyhole-shaped mound with a square front and a round rear. From the air, the outline is clear, and many are surrounded by water-filled moats.

Others are round or square. Their size and shape reflect the status of the people buried, and the style spread widely during the period. The era takes its name from them. The Kofun period follows the Yayoi and is associated with the growth of regional power centres, including the Yamato area in the Nara basin and Osaka plain. Studying kofun helps scholars understand how early states developed. Researchers group them by shape and size, which helps trace the spread of customs from region to region.

Shape, Size and Construction

Building a large kofun required enormous organisation. Earth was gathered and shaped in layers, often faced with stones and encircled by moats. Workers needed tools, food and leadership. The scale of the largest mounds shows a society able to mobilise many people over long periods. Interiors vary. Some mounds hold stone chambers reached by a passage, while others have simple burial pits.

Grave goods found in various tombs include mirrors, jewellery, weapons and horse equipment, giving clues about beliefs and contacts with the continent. Today, trees and grass cover many mounds, so from the ground they can look like wooded hills. Walking around the moat or viewing a model at a museum helps you appreciate the shape. Aerial photographs and information boards often show the original outline. Aerial photographs make the outlines much easier to read than a view from ground level.

Haniwa: The Clay Figures

Haniwa are clay objects that stood on and around the mounds. The earliest were simple cylinders, while later ones took forms such as houses, boats, horses, warriors, farmers and musicians. Their charm lies in the simple, expressive faces and the glimpses they offer of life long ago. Their purpose is thought to include marking and protecting the sacred space of the tomb, though scholars hold different views.

Many were arranged in rows along terraces. Some regions, such as the Kanto plain, have produced especially lively examples. You can see haniwa in museums across Japan, including major national collections and local museums near excavation sites. Replicas often stand on the mounds themselves. They are popular motifs on souvenirs, and the friendly shapes appeal to visitors of all ages. Children often enjoy spotting the different animals and figures in museum cases.

The Mozu-Furuichi Kofun Group

In the Osaka area, the Mozu and Furuichi tomb groups contain some of the largest kofun in Japan. The Daisen mound in Sakai, traditionally linked to Emperor Nintoku, is among the largest tombs in the world by area. Together the groups were inscribed on the UNESCO World Heritage list in 2019. Many of these mounds are managed by the Imperial Household Agency, so access to the mounds themselves is limited. Visitors normally walk around the moats and view them from designated spots, with signs explaining the site.

Scale is hard to grasp from the ground, so look for models and viewing points. Local museums and visitor centres in Sakai and Habikino provide displays, videos and sometimes viewing facilities. Some public buildings in the area offer views over the mounds, and bicycles can be a pleasant way to explore. Check official websites for current information. Allow a relaxed half day or more, since the mounds are spread across a wide area.

Other Places to See Kofun

Beyond Osaka, kofun appear throughout Japan. In Nara Prefecture, the Asuka area has several, including the stone-chamber tomb of Ishibutai, which visitors can approach to see the large stones. The area is also rich in temples and rural scenery, ideal for cycling or walking. In Saitama, the Sakitama Kofun Park preserves a group of mounds near Gyoda, with a museum displaying finds. In Miyazaki Prefecture on Kyushu, the Saitobaru group is another large concentration set in open landscape.

Many other regions have local parks with information. Access varies, so research each site ahead of time. Local tourist offices can recommend routes and seasonal highlights. Spring and autumn are comfortable for walking, while summer calls for water and sun protection. Prefectural museums frequently hold special exhibitions on local tombs, so check their calendars. Local visitor centres often supply maps showing the mounds within walking or cycling distance.

Practical Tips and Etiquette

Treat kofun as burial sites and places of respect. Stay on marked paths, do not climb restricted mounds and keep voices low near them. Follow signs about photography and drone use, which may be restricted. Public parks may allow closer access, but rules differ. Wear comfortable shoes, as paths around moats can be long. Bring water and a hat in summer. A map from the local visitor centre helps, and some places rent bicycles.

Take your time; the scale rewards slow exploring. Pair a visit with local food. Osaka and Sakai are known for many dishes, and Sakai is also noted for traditional knives and crafts. Nara offers its own regional specialities. A museum stop followed by a relaxed meal makes a satisfying day. Bring a camera, but remember that many mounds are best appreciated from a distance, where their full outline can be seen.

Why Kofun Matter

Kofun stand at the crossroads of archaeology, landscape and national history. They tell of ambitious leaders, skilled builders and links across the sea. They also remind visitors that ancient history sits quietly beside modern life: a mound can rise behind a residential street or a city park. Their gentle, green forms invite curiosity. For many people, discovering a kofun in a neighbourhood is a pleasant surprise, and reading about its story adds depth to a walk.

Whether you see a giant keyhole mound from a viewing point or a small round one in a park, take a moment to imagine the effort that created it. That sense of continuity is one of the quiet pleasures of exploring Japan. Taking time to read the signs turns a casual stroll into a small lesson in early Japanese history. The mounds also anchor local pride, and neighbourhood groups often care for them.

Frequently Asked Questions

What is a kofun?

A kofun is an ancient burial mound built in Japan mainly between the third and seventh centuries. Many are keyhole-shaped and surrounded by moats. The period is named after them. Their size and shape reflect the status of the people buried in them.

Can visitors go inside a kofun?

Most large mounds are closed to the public, and many are managed by the Imperial Household Agency. Some tombs with stone chambers, such as Ishibutai in Asuka, can be approached. Check official sites for access details. Entry is generally limited to protect the sites, but moats and viewing points allow close views.

What are haniwa?

Haniwa are clay figures and cylinders placed on and around kofun. Forms include houses, horses, warriors and farmers. They are displayed in museums across Japan and are popular as souvenirs. They are charming souvenirs and a favourite subject for museum displays.

Keep Exploring

More guides from Tokyo Paul: Sakai: Osaka's Knife-Making City, The Yayoi Period: Rice Farming Reshapes Japan and The Jomon Period: Japan's Earliest Pottery Culture.