The roofs are all turned the same way, into the wind of the valley. Ogimachi is a settlement of gasshō-zukuri farmhouses standing among paddy fields, and their great roof planes face in more or less one direction. The reason usually given is aerodynamic and thermal at once: the alignment lets the wind that runs down the valley pass over them, and puts sun on the pitch so that snow slides rather than sits.

Several houses are open inside, the Wada house among them, and climbing to the upper floors is how you see the timber — the roof frame is built from members far heavier than a visitor expects. Ogimachi was designated an Important Preservation District in September 1976, and from the viewpoint above the village the whole settlement can be taken in at once. The village as a whole has a population of about fifteen hundred, Takayama is roughly an hour away by car, and the winter snow exceeds two metres.

A gasshō roof is entirely re-thatched about once every sixty years. A single re-thatching requires hundreds of pairs of hands, which is why the village needed yui, the mutual labour arrangement, in order for any house to keep its roof at all — and it means the size of the roofs has effectively determined how the community had to organise itself. The great roofs that visitors photograph are also units of collective work. They are as large as a village of this population could manage between them, and no larger — which is a limit set by the number of neighbours available on the day, not by anything an architect decided.