Tokurenba Tomb

The Tomb and Its Place in History

Tokurenba Kofun is classified as a small round mound (koenfun) of the middle Kofun period, dated to the 5th century. It is one of the oldest known burial mounds in the former town of Tamayu (now part of Matsue City). Although much of the original earthen mound has been lost over the centuries, the burial chamber and its remarkable stone coffin remain intact at the site.

The 5th century was a transformative era in Japan. Powerful clans were consolidating influence, the Yamato polity was extending its reach across the islands, and elaborate burial mounds became a means by which local elites broadcast their status. In the Izumo region — long described in the ancient Izumo no Kuni Fudoki (the 8th-century gazetteer of Izumo) — these chieftains were closely tied to specialised industries, and few were as prestigious as jewel-making. The person interred at Tokurenba is generally thought to have been a local leader connected to the powerful jewel-producing community at the foot of Mt. Kasen.

Why It Was Designated a National Historic Site

The Tokurenba Kofun received its designation in February 1933, almost a century ago, on the strength of a single extraordinary feature: its stone coffin. Boat-shaped sarcophagi from this period are not unknown in Japan, but the construction technique used here is genuinely rare.

The coffin consists of a lid and a body. The lid was carved from a single block of stone, while the body — and this is the unusual part — was carved by hollowing out two separate stone blocks that were then fitted together side by side, much like the way some ancient Japanese ceramic coffins were assembled. In other words, the coffin combines two different traditions of stone-coffin manufacture: the "carved-out" (kuriake-shiki) method, in which a single block is hollowed out, and the "assembled" (kumiawase-shiki) method, in which separate panels are joined. According to the original 1933 designation document, "this type of stone coffin, combining both carved-out and assembled techniques, has very few comparable examples."

The stone itself is also locally distinctive. It is made of a zeolite-bearing volcanic rock (called fusseki-gan in Japanese) that occurs in a narrow band running from Tamayu to nearby Shinji. Selecting this particular local stone — rather than importing material from further afield — places Tokurenba squarely within the geological and cultural landscape of ancient Izumo.

Highlights and Things to Look For

The most striking moment for any visitor is simply seeing the coffin. Most kofun in Japan present themselves as tree-covered hills with little to look at on the surface, but at Tokurenba the centerpiece is right there in front of you.

The Wider Tamatsukuri Story

Tokurenba sits inside one of the most archaeologically dense and historically significant landscapes in western Japan. The Tamatsukuri area takes its name from tama-tsukuri, "jewel-making", and for good reason: from the late Yayoi period through the Heian period, this was a major production centre for the magatama and tubular beads (kudatama) that adorned the elites of ancient Japan.

The raw material came from Mt. Kasen, the very mountain whose foothills cradle Tokurenba. Its blue-green agate, known as "Izumo Stone", was prized for its rich colour, hardness, and fine grain. Magatama crafted from this stone have been excavated from kofun ranging from Hakodate in the north to southern Miyazaki in the south, attesting to a trade and gift-giving network that spanned the entire archipelago. According to one tradition, even the Yasakani no Magatama enshrined as one of the Imperial Regalia of Japan was crafted from Izumo Stone of Mt. Kasen.

More than thirty jewel-making workshop sites have been documented in the immediate area. Visiting Tokurenba alongside the Izumo Tamatsukuri Museum and the surrounding archaeological park is the best way to grasp the scale and significance of this ancient industry.

Visitor Information and How to Reach the Site

Tokurenba Kofun is located in a quiet residential area of Tamatsukuri. The site is administered by Matsue City and is freely accessible during daylight hours. There is no admission fee, no staff on duty, and no formal facilities — visitors are asked to behave respectfully, stay on the marked paths, and refrain from touching or climbing on the stone coffin.

The most convenient access is from JR Tamatsukuri-Onsen Station on the Sanin Main Line, from which the site is a short taxi ride or a roughly twenty-minute walk through the hot-spring town. Public bus and taxi services from JR Matsue Station are also available. The hot-spring district of Tamatsukuri Onsen makes an excellent base, and many visitors combine a morning of archaeology with an afternoon soak in one of Japan's oldest documented hot springs, mentioned in the Izumo Fudoki of 733.

Nearby Attractions

The compactness of the Tamatsukuri area means several remarkable sites can be visited in a single day on foot or by short taxi rides.

• Izumo Tamatsukuri Museum (Izumo Tamatsukuri Shiryōkan): The only museum in Japan dedicated specifically to ancient jewel-making, displaying tools, raw materials, finished magatama, and reconstructions of workshop scenes.
• Tamatsukuriyu Shrine: An ancient shrine dedicated to the deities of jewel-making, including a sacred "wishing stone" said to grant the prayers of those who place their hopes upon it. Within its precincts is a designated archaeological site of jewel-making workshops.
• Tamatsukuri Tsukiyama Kofun: Another nearby designated tomb, notable for its unusually shaped boat-shaped stone coffin — an ideal complement to a Tokurenba visit.
• Iwayaji-ato Kofun: A horizontal cave tomb with a multi-chambered structure, illustrating a different burial style of the period.
• Tamatsukuri Onsen: One of Japan's oldest hot springs, woven into the landscape of the jewel-makers themselves and famous for water said to beautify the skin.
• Mt. Kasen Agate Park (Menō Kōen): A small park where visitors can see preserved agate-mining tunnels and exposed agate veins in their original geological setting.