Question

How did port cities become rich​

Answer 1

Answer:

The thing that makes trading cities rich is the trading part. Think of it as a spider web. The outer area connects to other areas but together to other side resources have to go towards the center. All resources are going towards this trade center and as a result the trade center has all the resources coming to it and is able to use all of them where whereas the outer areas can't.

Furthermore, the center, the trading city, is the shortest distance between most points and as a result it's the fastest, safest, and cheapest route. If it decides to do something that blocks one side from trading with the other side, if the two sides wish to continue trading they have to travel a slower, longer, more dangerous, and as a result more expensive route.

This is why trading cities are rich and powerful.