Wani here does not mean crocodile. It is an old word for shark, written with characters that turn up in the story of the hare of Inaba, and it belongs to the Izumo side of the country. It survives in the mountains of northern Hiroshima in a way that it does not elsewhere.

Miyoshi and Shobara are a long way from any coast. They eat shark raw. The flesh carries urea and related compounds that suppress the bacteria of spoilage, so it resists going off in a way ordinary fish does not — two weeks on, people here will still cut it for sashimi. Before refrigeration, this was the only fish that could reach these valleys and still be eaten uncooked.

Plenty of places in Japan eat shark in some cooked form. An entire district eating it raw, as a matter of course, is particular to these few valleys. It is sliced and eaten with soy sauce and a good deal of grated ginger. Blanched briefly and dressed with vinegared miso is the other common way with it. Neither treatment makes any attempt to disguise what it is.

There is a saying here that without wani, neither the festival nor the new year properly arrives. A landlocked district built its celebration food around a sea creature, on the strength of one accident of chemistry. What was hardest to get is what ended up at the centre of the table.