Yokodai about 60 years ago and today

History of Yokodai

In the 1945-50 aerial photograph, many bright, thin bands reach in like the branches of a tree. They are paddies on the valley floors. The slopes of the hills, where small fields and woods lie in patches, fill the spaces between them. The frame corresponds to Yokodai in Isogo Ward, the City of Yokohama, Kanagawa Prefecture, but nothing that could be called a town appears in this photograph. There are six past eras you can go back to here, and between them the view of nothing but hills and the view of a town trade places.

Hills carved by valleys

The lowest point in this frame is the measuring point in the middle. Its elevation is 38.5 m. From there the height rises in all four directions, reaching 57.5 m in the south, 55.6 m in the west, 49.7 m in the north, and 47.1 m in the east. Within a range of about 1 km there is a difference of 19 m, and the low point is at the center. The center of the frame is a valley line. The station is at the bottom of the valley. Living on the hills and going down into the valley to take the train is the daily movement of this town.

In these hills spreading across the southern part of Yokohama, the valleys carved by rainwater branch out finely. The flat valley floors can be used for paddies, and the hilltops become fields and woods. The 1945-50 photograph shows this division of use appearing directly as a pattern on the ground. The hamlets cluster in small groups where the valleys join, and thin white paths follow the valley lines up into the hills. Not a single line in this photograph can be said to have been drawn with a ruler. The district name Yokodai, too, was newly given to match the later land preparation.

Even if you switch to 1961-69, about 20 years later, the view at the center hardly moves. The bright bands of the valley lines, the dense woods covering the hills, and the patches of fields are all still there. The change is in the upper right corner of the frame, where a block of long, narrow buildings lined up facing the same way and a town area cut into lots have appeared. It is on a different hill, more than 1 km from the center. On the left, the white road running from the top edge to the bottom edge has grown wider, and houses have increased along it. Nothing has yet been placed on the hills at the center.

Ground cut and filled

In 1974-78 the scene in the frame is replaced. At the center there is a block where long, narrow buildings line up while swinging their direction again and again. The buildings are aligned neither north-south nor east-west, and they form rows that bend partway and rows that face each other diagonally. The arrangement looks like arrow feathers set in a row. The buildings do not trace the landform. The center, which was a valley line, has turned into flat blocks, and the buildings are placed on it in the directions of the plans.

At the lower right of the same photograph, work remaking the ground appears in a half-finished state. On the slopes of the hills, bright beige bare ground connects across several valleys' worth, its outline is cut by straight lines and arcs, and the edges of steps and the curves of work roads can be read. It is a section where the traces of filling the valleys and cutting the ridges remain in their form from before they became a town.

At the lower left of the frame, too, rows of buildings with swinging directions stand in a still larger group. It is on a different hill from the block at the center, and the buildings here are more numerous. The hill at the upper right is filled with detached houses even where there were woods and fields in 1961-69, and the colors of the roofs are scattered among brown and blue. The direction of the lots also differs from place to place, in contrast with the orderliness of the block at the center. A wide band passes diagonally from the upper left to the bottom edge; no buildings attach to either side, and it runs straight across the boundaries of the blocks without changing width. You cannot tell in a photograph of this size whether it is a railway or a road.

The railway reached this valley in 1970. The Negishi Line was extended south from Isogo Station, and Yokodai Station opened as its terminus. The tracks were opened through to Ofuna Station in 1973, and the terminus became an intermediate station. The change from a 1961-69 photograph with not a single building to a 1974-78 photograph where they are already all in place took place on either side of this station's opening.

Bare ground turned to lawn

1979-83 appears in colors that are dark and sunken overall. The town area has filled in further, but the biggest change is at the lower right. On the slopes that were beige bare ground, long, narrow curving bands of lawn now follow the valley lines in a chain. Woods remain between the bands, and bright lawn and dark green alternate in rows. Ring shapes and lines that look like courses can be read, but you cannot tell the name of the facility from the photograph. It is an area where the surface left after the earth was moved settled into a use other than housing land. In the block at the center, streaks of shadow begin to enter between the buildings, and toward the south a bright square surface and a building with a roof one size larger are added.

1987-90 is a winter photograph with the ground sunk in light brown, and of the five eras up to 1987-90 it is the one where the outlines of the buildings are clearest. The combination of bent rows and rows facing each other diagonally can be counted one building at a time. You can also see that the shapes of the gaps opened between buildings are not the same anywhere. In the large group of rows of buildings at the lower left of the frame, the same way of thinking about the arrangement can be read. The bands of lawn in the valley on the right have sharper outlines, and the boundary with the surrounding woods has become clear.

A town where the ups and downs remain

In today's aerial photograph, most of the frame is town area. The rows of buildings at the center overlap the 1974-78 photograph in both position and direction, down to the angles at which they bend. Near the station, several buildings with large roofs have been added. The change is in the amount of green: the groves between the buildings have grown, and from above, white bands of buildings and green bands run alternately.

The side of the landform is worth a look too. The bands of lawn in the valley on the right remain in the same place in the same shape, and the woods around them also continue thinly. There are woods in the lower left corner and along the bottom edge of the frame as well. Even so, the paddies of the valley lines that covered the frame in 1945-50 cannot be found anywhere. The ups and downs that were cut away do not come back. If you follow how the streets curve and how the lots tilt, however, the directions of the filled valleys show through faintly. Even in a town made from plans, the shape of the landform underneath does not disappear completely.

The figure is 245,000 yen per square meter. This is the value recorded in 2022 in a residential area of Yokodai 4-chome, and it is also the lowest value in the series up to the 2026 publication of the official land prices (Chika Koji). The highest up to the 2026 publication is 295,000 yen in 2026, and comparing the two gives more than 1.2 times. The observation point is about 200 m from the location. Even within the same district, surfaces where ridges were cut sit next to surfaces where valleys were filled. The quickest way to check whether the assumptions for earth and sand or those for water apply is the hazard map published by the City of Yokohama.

Another place where a large residential area was built around the same time is Takashimadaira in Itabashi Ward, Tokyo. A town made by cutting hills and a town placed on flat low land leave completely different traces of land preparation in the photographs.