Bishamondai about 60 years ago and today

History of Bishamondai

Clusters of roofs lined up in tiers fill the upper half of the frame. The rows trace the contour lines in arcs, and thin shadows of retaining walls fall between them. This is Bishamondai in Asaminami Ward, Hiroshima, Hiroshima Prefecture. If you open the aerial photographs from the oldest era, these tiers are absent from the first two. The top of the hill is nothing but wooded ridges and small valleys, and houses line up only on the valley floor toward the bottom of the frame. The housing on the hill does not sit on flat land that was searched for and found, but on surfaces made by cutting.

A hill of only forest and a town on the valley floor

The name Bishamondai comes from Bishamonten. It seems to be a name given to the hill itself rather than one inherited from an old settlement on the hill. In the black-and-white 1945-50 photograph, most of the frame is forest. Ridges and valleys interlock finely, a shadow falls in each valley, and the surface of the hill looks wrinkled. Human work appears at the bottom and right of the frame, where finely divided farmland lines the valley floor and a river flows beside it. White sand and gravel appear widely in the riverbed, and the stream splits into several channels. The town continues long and narrow along the river, and the grains of roofs grow sparser the farther they are from the valley.

Even in 1961-69 the hill remains forest. The ridgelines and the notches of the small valleys become clear, and dark green covers the frame from the center to the north. On the right there is a long, narrow north-south valley, and bright terraced lots and a small settlement appear on its slopes. The lower half is farmland on the valley floor, and the shapes of the lots have hardly changed from the previous era. In the lower left, two straight lines cross the farmland on the valley floor for a long way. There are more than ten years between the two photographs, yet there is no visible change on top of the hill.

Cutting the ridges into tiers

1974-78 is the first era at this location in which the photograph is in color, and also the first era in which the look of the hill changes. A wide, bright flesh-colored surface appears at the upper center of the frame. It is a development site where the forest has been stripped away and the soil exposed; straight roads run through it, and the surface is divided into many sections. Inside the sections, thin parallel lines run regularly. They are the boundaries of the individual building lots; only the lines of the lots were drawn first, and not a single building has been built yet.

To the south, small roofs are starting to line up on tiers that follow curves. Further toward the front, tiers still of bare soil are cut in arcs. Building housing on top of a hill does not proceed by laying a single sheet of flat land, but by cutting the slope into many tiers along the contour lines, running a road along each tier and lining up building lots. The amount of soil from cutting the ridges and filling the valleys is large, but it is easier to line up houses than on a slope left as it is. This one photograph shows three kinds of tier at the same time: finished tiers, tiers where building has started, and tiers still being cut.

More than ten years until roofs filled it

In 1979-83, the bare surface is filled with small roofs. Rows of roofs line up layer upon layer along the tiers, and the direction of the rows matches the direction of the roads. A large flat-roofed building and a wide sports ground have been added at the edge of the plateau, and a school-like shape can be read. In the lower half of the frame the town on the valley floor is visibly denser, and a long, narrow bare band crosses it from east to west.

This location has no 1984-86 photograph, so the next photograph jumps to 1987-90. In the 1987-90 photograph, the center of the danchi (housing complex) is already built up, and only a few surfaces within the lots are empty. The east side catches the eye, with a white cut road winding through the forested slope and surfaces of cut soil spreading like branches. It is the scene of development moving on to the next slope. The bare band that crossed the valley floor has become a wide road, and in the lower right of the frame a junction drawing a large loop connects to it.

Even after the hill filled with roofs, no railway ran to this town. In 1994 a rail line opened, and Bishamondai Station was placed below the hill. The order was that the town came first with roads and cars, and the railway followed more than ten years later. Another housing area made by cutting hills in the same city of Hiroshima is Koyo New Town.

The height differences and the cut shape

In today's photograph, the rows of tiers have increased further, and the roof colors have changed to white and pale blue. In the middle of the danchi there are two school-like facilities, with long school buildings, large roofs that look like gymnasiums, wide earth-colored sports grounds and blue rectangular water surfaces. Bands of dark green reach in like fingers between the rows of houses. They are small valleys left uncut, continuing to the bottom of the hill while edging the rims of the tiers. The one wide surface that was empty in 1987-90 remains empty and pale. Conversely, the eastern slope that was cut white then has returned to green, and the traces of development are covered by trees and hard to make out. Large flat-roofed buildings and wide roads gather on the valley floor, separated from the rows of houses on the hill by bands of green.

Of the five measured points, the highest is the north one at 140.2 m. It falls on the forested ridge occupying the top edge of the frame. The lowest is the west one at 92.4 m; the center is 106.6 m, the south 100.0 m and the east 100.8 m. The difference is 47.8 m, directly showing the difference in height between the surface the danchi sits on and the mountains and valleys around it. The center value is the height on the tiers, and the four points around it pick up the slopes outside. Because this land was made by cutting slopes into tiers, rainwater runs down between the tiers and collects on the valley floor. The City of Hiroshima's hazard map shows the expected landslides and flooding district by district, so it is worth checking whether a place falls on the hill or on the valley floor.

The price record is recent. It began in 2016 at a survey point placed at a residential site in Yasuhigashi 2-chome, at 74,100 yen per square meter. There has been no year in which it fell since, and in 2025 it was 86,900 yen. In the record up to the 2026 official land prices (Chika Koji), the first year, 2016, at 74,100 yen is the lowest and the last year, 2026, at 90,000 yen is the highest, a difference of 15,900 yen. The survey point is about 659 m from this location.

If you open the five photographs in order, three stages, forest, bare ground and roofs, replace one another on the hill. The cut tiers remain as they are; that is the shape of this land, and the arcs drawn by the rows of roofs are the traces of construction roads that traced the contour lines.