Answer: Major trading cities grew along and near waterways.
Step-by-step explanation:
As trade increased between the eastern world and the western world during the renaissance, certain cities in Italy became major centres of trade and so were able to grow to nation state levels.
These cities such as Venice and Genoa were mostly built along or near waterways and as such, saw goods come into their ports and then people from all over Europe would come to these ports to trade thereby increasing their influence and size.