The money that raised the udatsu came from indigo. Minamimachi in Wakimachi is a merchant district built on the indigo trade, and the houses along it carry udatsu, the raised fire walls at each end of the roof. Awa indigo was grown on the flood plain of the Yoshino River, where the silt left behind by flooding did the work of fertiliser — an agriculture arranged in partnership with a river that periodically destroyed things.

The merchants who bought that crop and sold it on lived here, and they registered the scale of their earnings in the height of the wall they could afford, which is why the profile of the street varies house by house rather than running level. Wakimachi was designated an Important Preservation District in December 1988. There are indigo dyeing workshops and a museum nearby, and work on bringing empty townhouses back into use continues. Tokushima city is about an hour away by car, and since this is flat land beside the river, farmland and housing spread out around the old street.

Indigo stopped selling quite suddenly when synthetic dyes arrived. The trade thinned out, the merchants' business ended, and the walls stayed up — so this streetscape is a record of a moment when the clock stopped, preserved in the most expensive material the town had. Streets of unusually fine houses are usually like this. What you are looking at is the shape of something that finished, kept standing because nobody afterwards had either a reason to replace it or the money to try. The walls that were built to advertise success ended up recording the last year in which there was any.