The ends of the roofs are raised slightly. Along the main street of Mino, the merchant houses carry udatsu — party walls built up higher than the roof itself, so that the profile of the street steps up and down instead of running level. An udatsu is a firebreak, meant to stop flames crossing from one house to the next, and it cost money to build. Some households could raise one and some could not, which is the whole of the reason the street looks the way it does.

Mino was designated an Important Preservation District in May 1999, and what you notice on a walk is not that the udatsu are there but that they are all different heights. A short distance away at Warabi is the paper village, with hands-on papermaking and a display of hon-Minoshi, the local handmade paper, so the merchant town and the producing district sit within easy reach of one another. That proximity is not a coincidence: what these merchants mostly dealt in was paper, and the prosperity of the street and the workshops upstream were two ends of a single trade.

The unevenness of the roofline is the household accounts of a century, left in place. Levelling the udatsu would tidy the street considerably, and it would also delete the information: this row was not designed by anyone, it accumulated, house by house, as each family found itself able or unable to afford the wall. A ragged profile is what a street looks like when nobody was in charge of it, and the eye reads that unevenness as age even when it cannot say why. It is a record, house by house, of who had a good decade and who did not.