Quote Originally Posted by zentuit
In MTW, the other town/province also had to have a port; this is probably true here too. Although to determine this you'd need to send a spy, or hope you can see the other city's trade route. So its possible to determine if this is a requirement.
I do not think so. Each coastal city starts with a 'fishing village' where the port will eventually be. I believe the trade will go in through there if a port has not yet been built. That is merely an educated guess from memory of my campaign though, so no guarantees.