Fiore doesn't seem to be based on any particular map so much as it's based on A map.
The region is based on several very basic things that relate to the world in general, though the second of which is based on the world, not on a map at all. First of all, the four establishments are set basically on the compas points, North, East, South, and West, things present on absolutely any map. There are no other cities at all, and they are perfectly situated so that Win Town is North, Fall City is East, Ring Town is West, and Summer Land is South.
It was also pointed out to me by Alata, although I understood two or so of them, that the names of the cities are based on the seasons. spRING Town, FALL City, SUMMER land, and WIN(ter) Town.
