>>40574125Country side is extremely empty and flat for the most part. But the Wild Area isn't based on the "countryside" specifically, it's more based on Britains National Parks.
The southern, grassy parts of the Wild Area, considering their geography and location near "Motostoke" (an industrial town in the middle of the region), it's likely based on the Lake District and similar parks, and honestly it's not that far off. Those areas are effectively just lakes and fields with varying topography. Part of their appeal is being largely devoid of any sort of structure, with long sight lines mostly full of grass.
These are a popular location for both tourists and for locals, so it makes sense they'd apply it to the region for a Pokemon game too.
The walled city is a video game abstraction because obviously they can't have a real life sized city that naturally flows from city centre to suburb to country, but sharp changes from natural grassy areas to industrial zones are quite common.