Kanko Ibaraki, the prefectural tourism association, gives the usual peak here as early to mid-November. On another of its pages the same body narrows it further, to around the tenth of November. A band and a point, published side by side, which is a fair reflection of how tight the window is.

The falls themselves are a hundred and twenty metres high and seventy-three wide, and the water comes down a broad rock face in four distinct steps. That is where the older name comes from — Yodo-no-taki, the falls of four stages. In autumn the maples close in on both walls of the gorge and the whole face is framed rather than merely wet.

There are two places to look from, reached through a tunnel cut into the hillside. The first deck faces the falls square on and puts you close enough that the noise is the main event. The second is higher up, and from there the water and the coloured trees resolve into a single picture rather than two separate things. Most people use both, in that order.

The trees turning here are irohakaede and omomiji, with yamaurushi, mizunara and shiraki mixed in, which is why the colour is uneven rather than uniformly red. The viewing facility keeps set hours and they change with the season, so check before you drive out. Daigo is a small town in the north of the prefecture, and the falls are its centre of gravity in November.