On land where water springs up of its own accord when you dig the ground, a 100,000-koku castle town opened, and a traveling haiku poet tied off the Narrow Road to the Deep North here. Ogaki’s numbers are the record of a provincial city that, standing upon abundant underground water, quietly matures.
A city in the western part of Gifu Prefecture, with its origin in a castle town that opened on a plain where the underground water of the Ibi River springs up abundantly. The population has continued roughly flat, at about 150,000 to 160,000 since 2000, with no large rise or fall. What I (Atlas) want to read here is not the impression "the city of water," but the causal thread: how the history of self-springing water, the castle town and the highway is translated into today’s aging and the number of children.
01 · Trace the present Ogaki City in its numbers
In the latest Population Census the population is about 158,000 (158,286 in 2020). From 150,246 in 2000 it rose to 161,160 by 2010, then turned to gentle decline. That the number of schools rose from 17 to 22 from 2005 to 2006 is owing to mergers with surrounding towns and villages.
What I want to note here is that, behind a total population that does not move greatly, the content of the ages is moving. The share aged 65 and over rose more than ten points over twenty years, from 16.9% in 2000 to 27.5% in 2020. Those under 15 fell by some three thousand, from 23,127 to 20,339. The household-with-children share is 23.4% (2020). The number of elementary schools has long stayed at the post-merger 22, the Childcare Waitlist has been zero in recent years, and the Fiscal Capacity Index was 0.83 in fiscal 2023. The figure of a provincial city that quietly grows older while keeping flat appears in the numbers. Why it takes this shape cannot be read without going back over the history of the water and the castle town.
Source: Population Census (Statistics Bureau, MIC) / Real Estate Information Library (MLIT) / Local Government Finance Survey (MIC) / Childcare Facility Status Report (Children and Families Agency)
02 · Self-springing water, the castle town, the Narrow Road to the Deep North — the history behind the numbers
Ogaki’s skeleton is set, first of all, by the water flowing beneath the ground. This whole area is an artesian belt rich in the underground water of the Ibi River, and wells where groundwater springs up of its own accord, without using any power, were once in many households. Even now, spring water gushes forth in places across the city. That it is land where water is abundantly obtained is the ground for calling Ogaki "the city of water (Suito)," and was also a condition for a castle town to open.
Upon that water, a castle town was built. Ogaki Castle is said to have been founded in 1535, and at the Battle of Sekigahara, Ishida Mitsunari of the Western Army made it his base. After the warring states had passed, in the Edo era from 1635 onward, the Toda clan continued as castellans of 100,000 koku until the Meiji era, and a castle town centered on the castle prospered. A 100,000-koku castle town on a plain blessed with water — this became the foundation of the city’s centrality.
And one more thing that left its name on this city is the highway and haiku. Around the Genroku era, Matsuo Basho chose Ogaki as the place to tie off the long journey of the Narrow Road to the Deep North. It is told that he set off from here by boat for his home of Iga, and Ogaki came to be known as "the place where the Narrow Road to the Deep North is tied off." A castle town opened upon abundant water, and the memory of the highway and haiku overlapped — this city’s shape stands upon the history of self-springing water and a 100,000-koku castle town.
Source: Ogaki City (Ogaki, the City of Water) / Ogaki City (Ogaki Castle) / Ogaki City (history and geography — overview)
03 · Behind the flat figure, the city quietly grows old
What characterizes Ogaki City is that, while the total population is kept roughly flat, the aging rate has risen more than ten points over twenty years. This is the form common to mature provincial cities, where, with no great inflow or outflow, the generations already living go on aging just as they are. The actual number of children fell by some three thousand, but not as a sudden shrinkage — it stays at a gentle thinning.
The numbers of living infrastructure also mirror this gentleness. The number of elementary schools, after becoming 22 with the mergers, long did not move, and even against the fall in children the school network is largely kept. The Childcare Waitlist has stayed zero in recent years. But this is less the result of children continuing to flow in than a side where supply and demand balance amid a gentle thinning of children. A provincial city that prospered as a castle town, after rising once in population after the war, has now entered a stable period with little inflow or outflow. The total population is kept, the children gently decrease, and only the aging advances. The three movements look separate, yet are no more than separate faces of a single make-up: that, with no great inflow or outflow, the already-resident generations go on aging just as they are.
Source: School Basic Survey (MEXT) / Childcare Facility Status Report (Children and Families Agency) / Population Census (Statistics Bureau, MIC)
04 · A castle town upon water
Ogaki holds several functions of its own. One is the "city of water" that opened upon an artesian belt, where wells and spring water that gush up groundwater without power still remain in places across the city. Another is the 100,000-koku castle town raised around Ogaki Castle, which has supported its character as the center of the Seino region. And as the place where Matsuo Basho tied off the Narrow Road to the Deep North, it carries on to this day the memory of the highway and haiku.
Ogaki is a castle town that opened upon abundant underground water. From land blessed with water, to a 100,000-koku castle town, to the central city of Seino — the condition that "there was a plain where the underground water of the Ibi River springs up of its own accord" drew in the castle town, and that castle town gave rise to the city’s centrality. Not a visible landform, but the condition of water flowing underground, drew in the castle town and left its character as wells still springing across the city to this day.
Source: Ogaki City (history and geography — overview) / Ogaki City (Ogaki, the City of Water)
05 · Atlas note — the flat figure is not stagnation but the stillness of a balance struck upon spring water
Lay out Ogaki’s numbers and the indicators of a mature provincial city line up: a flat population, gently decreasing children, a ten-point rise in aging, and a fiscal capacity of 0.83. But seen with the eye accustomed to ledgers, before these quiet stabilities lies the history of land blessed with self-springing water and a 100,000-koku castle town that opened there. The present flatness can be read as the flatness of a city that, having kept its centrality as a castle town, reached, after a post-war rise in population, a state where inflow settled down.
Reading the city’s numbers over again with the eye that reads ledgers, it is the flat population — a seemingly motionless indicator — that I most want to read with care. A flat figure is not stagnation. On land where water springs up of its own accord when you dig the ground, a 100,000-koku castle opened, and a city that kept its centrality as a castle town reached, after a post-war rise in population, the balance arrived at once inflow settled down. The ledger of some three hundred years, having come to where inflow and outflow are balanced, is folded behind the single word "flat." Not a visible landform, but the condition of water flowing underground, drew in the castle town and left its character as wells still springing across the city. What I (Atlas) picked up from Ogaki’s numbers is not a lack of movement, but the stillness of a balance struck upon that spring water.
Source: Population Census (Statistics Bureau, MIC) / Ogaki City (history and geography — overview) / Ogaki City (Ogaki, the City of Water)
Editor’s note: all figures and sources are drawn from official statistics. The prose follows Atlas’s voice, and AI (atlas-handcrafted-reverse-v1 (Daiki 2026-05-29)) handled the shaping of the text. Evaluative or predictive language (such as “a good buy” or “attractive”) is intentionally left out. Revision id: wave8b_5