From Japan Heritage (Agency for Cultural Affairs).
In the Izumo area of eastern Shimane, iron making called tatara, using iron sand and charcoal, has been active for about 1,400 years. It is a way of making iron that developed on its own in Japan.
The Izumo-no-kuni Fudoki, written in 733, says that the iron made in this land is hard and the best for making all kinds of tools.
In the Oku-Izumo area, granite containing good iron sand is spread widely, and there were large forests for making charcoal. Iron makers gathered there for these resources.
At its peak, from the late Edo period to the Meiji era, about 80% of Japan’s iron was made at the foot of the Chugoku Mountains, centered on this area. The area of the old Matsue domain alone made nearly half of Japan’s iron.
A local story tells of Kanayago-kami, the god of iron making, who came down on a white heron to a katsura tree and taught people how to make iron. The head shrine of Kanayago Shrine stands here.
To collect iron sand, people cut into mountains and washed the soil down water channels. This is called kanna-nagashi. They needed so much iron sand that they cut away a great many mountains.
The cut land was not left as it was. Using the ponds and channels from kanna-nagashi, people turned it into farmland, making terraced rice fields that run for more than 1 km. Small hills left standing in the fields are sacred places, such as shrine woods and graves, that people did not cut away.
Most of the leftover soil settled downstream and formed wide rice-growing plains, such as the Izumo and Yasugi plains.
The forests for charcoal were used again and again in a cycle. Tatara supported Japanese society as a sustainable industry in which people and nature lived together.
Today, the fire of tatara still burns in this area, the only place in the world where it does. Sugaya Tatara Sannai is the only tatara workplace from the Edo period that still stands.
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