There’s no catchment radius because as long as the have a time advantage using this station the inhabitants will use it if I got that right. So if you place stations like busstations close to each other people won’t have to walk that far and are more likely to use your bus. But if you have only one train station in town and some people have to walk for quite a long time to get there, they still might use it to travel in other cities. However I already asked if we could have a optional layer in the game which shows how long it takes (by foot) from each house to walk to the next station.
Train Fever
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