Trace the danchi called the largest in the East through aerial photographs

Published: August 11, 2026 / About 12 min read

The place called "the largest danchi in the East"

Kori Danchi (public housing complex) in the City of Hirakata, Osaka Prefecture, is a residential area that was called the largest danchi in the East when occupancy began in 1958. The danchi was built on the former site of a gunpowder manufacturing facility of the former Imperial Japanese Army, the Kori Works of the Tokyo No. 2 Army Arsenal. In the aerial photograph from around 1936-42, the hilltop is covered with overlapping diagonal lines and the ground surface cannot be read, but in the next one, from 1945-50, the skeleton of the plateau appears clearly. Parallel valleys form bands of black woodland, the ridges between them stand out as bright surfaces, and long, narrow buildings line up at equal intervals along the ridges. A straight road crossing from east to west slightly above the center can also be seen.

The Japan Housing Corporation, established in 1955, chose this plateau as its site. In the 1961-69 photograph, the center of the frame has been almost entirely replaced by rows of residential buildings. Groups of a few buildings are turned in different directions, and rows opening like fans, rows drawing arcs, and small buildings stretching arms in three directions are mixed together. A design that combined several types of residential buildings was tried here and later became a model for danchi. The streets curve along the terrain, and you can read a way of thinking different from pushing a grid through flat land.

Every starting point was "land that was not yet a town"

Large danchi share not so much the number of dwellings as the character of the land before them. Several thousand dwellings could be placed at once precisely because there was a large block of land outside the town.

Tokiwadaira Danchi in the City of Matsudo, Chiba Prefecture, was built by leveling fields and woodland on top of the Shimosa Plateau. There was flat, wide land in the 20 km range from the city center, and the Shin-Keisei Line crossed the plateau from east to west. Occupancy began in 1960, and the name of the station was also changed from the name of the village before development to Tokiwadaira.

The land before Takesato Danchi in the City of Kasukabe, Saitama Prefecture, was paddies. In the 1961-69 photograph, paddies cut into strips continue from corner to corner, villages covered with homestead woods sit only here and there along the roads and rivers, and not a single residential building appears. Occupancy began in 1966.

The land before Takashimadaira Danchi in Itabashi Ward, Tokyo, was lowland paddies along the Arakawa River called Tokumarugahara. In the 1961-69 photograph too, the area from the left half of the frame to the center is still paddies, and factories and warehouses line up along the waterway to the north. In 1968 the subway extended north and stations were placed in the area, and occupancy began in 1972. It is a danchi that the tracks had reached first.

The land before Otokoyama Danchi in the City of Yawata, Kyoto Prefecture, where occupancy began in the same year, 1972, was hill forests and valley paddies. Across three eras of photographs, from around 1936-42, 1945-50, and 1961-69, the outline of the hills hardly moves. Irrigation ponds made by damming the valleys are scattered as black water surfaces, and small terraced paddies branch and reach deep into the valleys.

The change happens across a single photograph

The thing to see in a danchi is less its finished form than the before and after of the change. If you advance one era, the moment when paddies and forests turn into blocks remains, as if caught between two shots.

At Takesato Danchi, the moment you advance from the paddies covering everything in 1961-69 to 1974-78, rows like bars of the same length laid diagonally appear all at once. Between the buildings the ground is blank white, and almost no tree shadows fall. You can tell it is a town where the trees were just planted. At the eastern and southern edges of the danchi, the strips of paddy still come right up to just outside the site.

In the 1974-78 photograph of Otokoyama Danchi, surfaces of soil where the hills were cut run diagonally across the frame, and many of the divided lots are still empty. In the next era, 1979-83, the color of soil disappears, and around the core of the rows of residential buildings placed earlier, the surroundings are packed with houses. The speed at which the hills are replaced by a residential area at an interval of just one era comes across best if you look at the two photographs in a row.

In the 1974-78 photograph of Takashimadaira Danchi, the grid of paddies disappears, slab-shaped buildings stand in many rows, and two sports grounds with oval tracks appear. From northeast to southwest, a wide road and an elevated railway run as two bands. Tokiwadaira Danchi is one step older: in the oldest photograph you can go back to, 1961-69, the bow-shaped rows of buildings already appear in their finished form. The wild land before grading belongs to a time the photographs do not reach.

The number of photographs you can go back through differs by danchi

Even among the same five danchi, the number of photographs you can trace is not the same. Takashimadaira Danchi has all seven eras from around 1936-42 to 1987-90, the most of the five. Because there are three eras before occupancy began in 1972, you can compare the time when it was paddies in three stages. Kori Danchi has six, from around 1936-42 to 1984-86, and Otokoyama Danchi five, from around 1936-42 to 1979-83, and both keep two or more photographs of the hills before occupancy.

Tokiwadaira Danchi and Takesato Danchi have five each, from 1961-69. At Takesato, the oldest photograph is still paddies everywhere, so only one photograph of the land before occupancy remains. At Tokiwadaira, the oldest photograph already shows the danchi, and there is no way to check the fields and woodland before grading in a photograph. The way the year occupancy began and the order of the photograph eras happen to line up decides whether you can witness the starting point of a town.

The face of the "earlier land" in the texture values

If you calculate the texture value of the built-up area from the pixel differences of the aerial photographs, the movement from the 1961-69 photograph to the photograph as of 2026 becomes a number. Kori Danchi goes from 21.2 to 47.4, Tokiwadaira Danchi from 19 to 36.7, Takesato Danchi from 18.2 to 35.7, Takashimadaira Danchi from 16.1 to 38.2, and Otokoyama Danchi from 12.5 to 31.8.

The values to note are the starting points more than the end points. The lowest, 12.5, was Otokoyama, which was hill forest, and the next lowest, 16.1, was Takashimadaira, which was paddies. A photograph with a small value is also a record that the same texture covered the view. Hills with continuous tree crowns and paddies cut in the same direction appear from above as surfaces with little variation.

Conversely, at Kori Danchi, whose starting point is the highest at 21.2, residential buildings already stood in rows by 1961-69. Its end point of 47.4 is the highest of the five danchi and reaches more than twice its starting point. The reading that the low starting point tells of the land before is a clue when you compare photographs of danchi.

If you overlay the 1961-69 photograph and the photograph as of 2026 and take the mean pixel difference, the order of the values changes a little. Takashimadaira Danchi is the largest at 26.9, followed by Takesato Danchi at 22.7, Kori Danchi at 21.4, and Tokiwadaira Danchi at 19.9, and Otokoyama Danchi is the smallest at 15.5. The two that replaced lowland paddies with towns line up at the top, and Kori and Tokiwadaira, whose 1961-69 photographs already show residential buildings, come after them. Even for the same danchi, the height of the end point and the size of the change come in different orders.

Danchi on plateaus and danchi on lowlands

The difference in the land before also remains in the terrain figures. In the measured elevations, Takashimadaira Danchi, converted from paddies, is 3.4 m near the center, and Takesato Danchi is 5.2 m with 4.1 m on the south side; the height barely moves within a range of less than 1 km. It is low, flat land close to the bottom of the Kanto Plain.

On the other hand, the danchi raised from plateaus and hills are on a different scale. Tokiwadaira Danchi is 26.8 m on top of the Shimosa Plateau, Kori Danchi 25.9 m on top of the plateau, and Otokoyama Danchi 45.3 m on top of a ridge. At Otokoyama, the measuring points to the north / south / west line up from 46.9 m to 51.3 m, but the measuring point to the east alone drops to 31.2 m. The figures also show that the town sits on a slope falling in one direction toward the lowland of the Kizu River.

Even if you lump them together as "danchi", the way rainwater gathers often follows the valley lines before they were cut or the surfaces that were filled. Open the Hazard Map Portal Site of the Ministry of Land, Infrastructure, Transport and Tourism and the hazard maps that each city publishes, and trace once which valley the roads you use are an extension of.

Forty years recorded in the official land prices

The official land prices (Chika Koji) around the danchi draw the time since occupancy began directly as lines. The values below are all per square meter and are the actual figures at each point in time.

At Takashimadaira, the 2026 value stands at about 1.5 times the starting point of 1983, and Otokoyama is below its starting point. The range of the record differs completely by danchi, and you cannot describe the whole from a single line.

The same form scattered across the country

Towns of the same form exist across the country. Shogen Danchi in Izumi Ward, the City of Sendai, Miyagi Prefecture, is on a hill at an elevation of 71 m, and three eras are available: 1961-69 / 1974-78 / 1984-86. Its texture value moves from 11.9 to 36.1, and its low starting point has the same character as Otokoyama. The official land price at Shogen 7-chome, about 560 m away, fell from 87,300 yen in 2002, when the record starts, to 64,900 yen in 2012-2013, and 138,000 yen in 2026 is the highest value up to the 2026 publication.

Makomanai in Minami Ward, the City of Sapporo, Hokkaido, is sloping land, 94.4 m at the center and 110.7 m on the south side, and you can advance through three eras from 1961-69. The official land price at Makomanai Izumimachi, about 330 m away, moved from 100,000 yen in 2014 to 170,000 yen in 2026. Yokodai in Isogo Ward, the City of Yokohama, Kanagawa Prefecture, has five eras and goes back as far as 1945-50.

Akeno Danchi in the City of Oita, Oita Prefecture, has only two photographs, 1961-69 and 1974-78, but its texture value goes from 8.7 to 34.2, and its starting value is even lower than those of the five danchi. Murasakibaru Danchi in the City of Kagoshima, Kagoshima Prefecture, also has two, and here the mean pixel difference between the 1961-69 photograph and the photograph as of 2026 reaches 36.6, larger than for any of the five danchi.

Compare with the rows of residential buildings as landmarks

If you look only at the finished form, every danchi looks like a repetition of similar residential buildings. If you go back one era, an entirely different landscape was there: a former gunpowder factory site, paddies, and hill woodland.

The things that remained after more than half a century since occupancy are the same at every danchi. The trees between the buildings have grown, the surrounding paddies and fields have been replaced by town, and still only the positions and directions of the buildings match the first photograph. The five danchi all arrive at one point: only the arrangement of the buildings remains. If you move back and forth between photographs across the year occupancy began, you can see what terrain the rows of residential buildings were placed on, and the origins of the town come into view.

The prices in this article are actual examples at each point in time and do not reflect market prices after the article was written.