I haven't tested it, this might actually be possible by making the seas connect in provinces.bmp but raising the heights of this connection in topology.bmp to that of a land province. Maybe? Only reason why I suggest this is because I've done the opposite: I've had a land province look like water by making its colour in topology match that of the sea.
Feel free to prove me wrong, I know that'd save me a lot of time![]()
Yes, that might work although all countries would be able to navigate through it unmolested. It is better than what we currently have.
If I do this I will also make the Nile sea province(s) up to at least Memphis. I am currently reading Lords of the Sea and the Athenian navy was able to sail right up to Memphis where apparently there were substantial shipyards.
In Vicky 2 they have a trigger "is_canal_enabled" and an effect "enable_canal".