Here is an article (published in 2008 on Cybergeo) by César Ducruet on the links between specific port dynamics and wider urban dynamics, as seen from a sample of 330 cities encompassing all the oceans.  One of the conclusions of this work is the singularity of Europe, a continent in which the port cities are relevant, but depend in the hierarchical scale on inland cities (and specifically those of the “blue banana” between London and Milano).