These trees were planted on a shogun's orders, or so the story goes. The tourism association for Sumida ward credits Tokugawa Yoshimune, the eighth shogun, with the planting along this stretch of river. On the Sumida side there are three hundred and forty-three of them, mostly Somei-yoshino, running about a kilometre between Azuma bridge and Sakura bridge. The association does not say how many stand on the Taito side opposite, only that the planting follows both banks for the same stretch, which is the fact that matters once you are there.

The point of the place is that there are two rows, one on each bank, with the river between them, and you can only ever stand on one of them.

Walk one side and you have flowers over your head and flowers across the water at the same time. The near ones you look up into. The far ones you see side-on, at a distance, as a line rather than as trees, with the current moving underneath them.

It is the same avenue, but which bank you stand on changes what it is. From the middle of a bridge you get both at once, which sounds like the best position and is in fact the most crowded. The timing given on this page is not the ward's; no average peak is published, so it comes from the weather record for Tokyo.