Japan Maritime Self-Defense Force (JMSDF) Kure Museum

This guide to the JMSDF Kure Museum opens with a decades-old navy habit: every Japanese warship serves curry on Fridays, a way of marking a week at sea when the days blur together, especially aboard a submarine with no windows and no sunrise. It follows how each vessel guards its own recipe like a state secret, needing a captain's sign-off before it counts as that ship's curry, and how sailors based in Kure have passed roughly two dozen of those recipes on to local restaurants. You'll hear about the museum cafe's own submarine-shaped plate, piled with rice, two meat patties and a small paper flag. Try it before you go looking for the real hull it is modeled on.