The river that runs through this town is said to be the stage of the legend of a great serpent. In the mountain folds along its middle and upper reaches, furnaces that once made iron from iron sand and charcoal — the furnaces of tatara — burned in great number. Scraping the mountains for iron sand, charring the trees of the valleys — the work of making iron has shaped this land’s mountains and rivers. The river of myth, and the memory of the tatara: an old story and an old industry, both held in these mountain folds. Six towns and villages were bound into one, and this city was born. This tatara land on the upper reaches of the river of myth has lost population while binding the six together. Unnan-shi’s numbers record a town inscribed with the history of a merger of six towns and villages, the river of myth, and the memory of the tatara.
A city in eastern Shimane Prefecture, opening across the middle and upper reaches of a river said to be the stage of the great-serpent myth. In 2004 it was founded when six towns and villages were bound into one. After its founding the population moved from 44,403 in 2005 to 36,007 in 2020. What I (Atlas) want to read here is not the sign “a city in the eastern part of the prefecture,” but the causal thread: how the history — a merger of six towns and villages, the river of myth, and the memory of the tatara — is translated into today’s population and finances.
01 · Pin down the population and finances of Unnan-shi in its numbers
In the 2020 Population Census the population of Unnan-shi is 36,007 — a city of about thirty-six thousand. Because this city was founded in 2004 when six towns and villages were bound into one, the statistics treat the period after that founding. The post-founding population fell from 44,403 in 2005 to 41,917 in 2010, 39,032 in 2015, and 36,007 in 2020.
Looking inside the figures, the shape of a city on the upper reaches of the river of myth growing older appears. The share aged 65 and over rose from 31.4% in 2005 to 36.5% in 2015 and 40.1% in 2020, reaching four in ten. Households with children make up 21.8% (2020), on the higher side for a mountain-fold city, and the crude birth rate was 5.7 per thousand in 2020. The Childcare Waitlist was zero in both 2024 and 2025. The Fiscal Capacity Index was 0.25 in fiscal 2023 — its own tax revenue covers only a quarter of expenditure, a level with a large dependence on the local allocation tax. The numbers show the tatara land on the upper reaches of the river of myth losing population while binding the six together. Why it takes this shape cannot be read without tracing the history of its position on the upper river, the memory of the tatara, and the merger of six towns and villages.
Source: Population Census (Statistics Bureau, MIC) / Local Government Finance Survey, Fiscal Capacity Index (MIC) / Childcare Facility Status Report (Children and Families Agency) / Real Estate Information Library (MLIT)
02 · The upper river of myth, tatara iron-making, mountain-fold life, the merger of six towns and villages — the history behind the numbers
This town’s skeleton is set by its position on the upper reaches of the river of myth, by tatara iron-making, by mountain-fold life, and by the merger of six towns and villages. The opening layer is the upper river of myth. This land, in the eastern part of Shimane Prefecture, spreads across the middle and upper reaches of a river said to be the stage of the great-serpent legend. In the north a plain opens near the confluence of the rivers; to the south it reaches the Chugoku Mountains. The upper river of myth was this town’s foundation.
In these mountain folds, the furnaces of the tatara burned. Tatara iron-making — drawing iron from iron sand and charcoal — flourished here, and the work of scraping the mountains for iron sand and charring the valley trees shaped this land’s mountains and rivers. The river of myth and the memory of the tatara have been inscribed in these mountain folds. The path by which it became a city mirrors the town as well. In 2004 the six towns and villages were bound into one to form the present city, widening the area it measures. The upper river of myth, tatara iron-making, mountain-fold life, and the merger of six towns and villages — this town’s form stands on the history of the tatara and the merger, inscribed by the upper reaches of the river of the great-serpent legend.
Source: Unnan City / tatara iron-making (in eastern Shimane Prefecture, on the middle and upper reaches of the Hii River — the river of myth; tatara iron-making and charcoal-burning once flourished in the mountains, and the land reaches the Chugoku Mountains to the south — overview) / Unnan City / the Hii River (the municipal area spreads across the middle and upper reaches of the Hii River system; in the north a plain opens near the confluence of the Hii River and its tributaries; the Hii River is said to be the stage of the great-serpent myth — overview) / Unnan City (founded on 2004-11-1 by a new merger of six towns and villages — Daito, Kamo, and Kisuki of Ohara District plus Mitoya, Kakeya, and Yoshida of Iishi District; statistics treat the period after its founding, from 2005 — overview)
03 · On the tatara land of the upper river of myth, losing population while binding six together
What characterizes Unnan-shi is that, while carrying the memory of the tatara, it has lost population even after binding the six together. From the 44,403 of 2005, after its founding, to the 36,007 of 2020, it lost some eight thousand over fifteen years. Even in this land of mountain folds where the furnaces of the tatara once burned, one can read that some of the younger generation moved toward the larger cities and the whole town grew older. That the share aged 65 and over reached 40.1% in 2020 is the sign of that.
Meanwhile the Childcare Waitlist was zero in both 2024 and 2025, and households with children make up 21.8% (2020), on the higher side for a mountain-fold city. The crude birth rate was 5.7 per thousand in 2020. A Fiscal Capacity Index of 0.25 is a level whose own tax revenue covers only a quarter of expenditure, showing the large dependence on the local allocation tax common to mountain-fold lands. Deep aging and a higher-than-usual share of households with children — the aging rate that has reached four in ten and the 21.8% share of households with children, high for a mountain-fold city, would not ordinarily move in the same direction. That these two coexist is where the circumstances of a mountain-fold city built by binding six towns and villages show through.
Source: Population Census (Statistics Bureau, MIC) / Local Government Finance Survey, Fiscal Capacity Index (MIC) / Childcare Facility Status Report (Children and Families Agency)
04 · The upper reaches of the river of the great-serpent legend held the memory of the tatara
In Unnan, several functions are layered upon the land of the upper river of myth. One is the history of the upper river of myth: in the eastern part of Shimane Prefecture, spreading across the middle and upper reaches of a river said to be the stage of the great-serpent legend. Another is its character as a tatara land, where iron-making from iron sand and charcoal flourished and shaped the mountains and rivers themselves. And it holds the face of mountain-fold life, with hamlets gathered on the plain at the confluence and along the edge of the Chugoku Mountains. The land of the middle and upper reaches where the great-serpent legend is told nurtured the work of the tatara that drew iron from iron sand and charcoal, and scattered the hamlets through the mountain folds.
On the middle and upper reaches where the great-serpent legend is told, tatara iron-making from iron sand and charcoal took root and inscribed the very shape of the mountains and rivers. The 2004 merger of six towns and villages bound into one city the hamlets scattered on the plain at the confluence and along the edge of the Chugoku Mountains. Eastern Shimane Prefecture, the upper river of myth — to read Unnan, one enters from this single tract where the myth and the memory of the tatara fold over one another.
Source: Unnan City / tatara iron-making (in eastern Shimane Prefecture, on the middle and upper reaches of the Hii River — the river of myth; tatara iron-making and charcoal-burning once flourished in the mountains, and the land reaches the Chugoku Mountains to the south — overview) / Unnan City / the Hii River (the municipal area spreads across the middle and upper reaches of the Hii River system; in the north a plain opens near the confluence of the Hii River and its tributaries; the Hii River is said to be the stage of the great-serpent myth — overview) / Unnan City (founded on 2004-11-1 by a new merger of six towns and villages — Daito, Kamo, and Kisuki of Ohara District plus Mitoya, Kakeya, and Yoshida of Iishi District; statistics treat the period after its founding, from 2005 — overview)
05 · Atlas note — reading the thickness of how the tatara scraped the mountains and rivers
Lay out Unnan’s numbers and the indicators of a mountain-fold city line up: a municipal area built by binding six towns and villages, an aging rate of 40.1%, a household-with-children share of 21.8%, fiscal capacity of 0.25. But my (Atlas) interest, which wants to trace back to the work of the land behind the figures, turns to the fact that this town has carried an old industry — tatara, the making of iron from iron sand and charcoal — that uses the mountains and rivers directly. Tatara iron-making was work that took the land itself as its material: scraping the mountains for iron sand, charring the valley trees. The industry of making iron changed the very shape of this land’s mountains and rivers. That the industry of a land inscribed the very scenery of that land — this chain shows a thickness that does not appear in the town’s figures.
One more thing to weigh is that the share of households with children, at 21.8% in 2020, is on the higher side for a mountain-fold city. That, in a mountain-fold city whose aging rate has reached four in ten, the share of households with children is still on the higher side, can be read as mirroring a side where this land has continued its own efforts to support child-rearing. Even in mountain-fold cities where aging advances, the share of households with children is not uniform — local efforts can bear on the share of young households. This reading does not surface from gazing at the single figure of an aging rate. On the upper reaches of the river of myth, the memory of the tatara that scraped the mountains and charred the valley trees to draw out iron — whether to set that history close to one’s own life and read it, or to pass it by as a distant sign, the thread from there lies not with the writer, but with you, the reader.
Source: Population Census (Statistics Bureau, MIC) / Unnan City / tatara iron-making (in eastern Shimane Prefecture, on the middle and upper reaches of the Hii River — the river of myth; tatara iron-making and charcoal-burning once flourished in the mountains, and the land reaches the Chugoku Mountains to the south — overview) / Unnan City / the Hii River (the municipal area spreads across the middle and upper reaches of the Hii River system; in the north a plain opens near the confluence of the Hii River and its tributaries; the Hii River is said to be the stage of the great-serpent myth — overview) / Unnan City (founded on 2004-11-1 by a new merger of six towns and villages — Daito, Kamo, and Kisuki of Ohara District plus Mitoya, Kakeya, and Yoshida of Iishi District; statistics treat the period after its founding, from 2005 — overview)
Editor’s note: all figures and sources are drawn from official statistics. The prose follows Atlas’s voice, and AI (atlas-handcrafted-reverse-v1 (wave35-west 2026-06-04)) handled the shaping of the text. Evaluative or predictive language (such as “a good buy” or “attractive”) is intentionally left out. Revision id: wave35w_