The (three?) foreign ports also count as producing an infinite amount of each good. You can buy anything from the foreign ports, but the cost to do so increases the further away from their corners of the board you get (because you need to pay /TransportCosts).
Okay, makes sense. The big question now is: are production facilities limited? If not, then if a player assembles three production routes they have sole control over, the rules shouldn't let a player assemble a large number of large cities for free in that area. --AC
I suspect the answer should be that it becomes worth it to the other players to build a city in that same area.--DR