The locale that looks easiest to set up a base is right where a river joins a sea. Not sure if its an outlet or inlet as no current that I can tell. Logs in the river float in place. I notice trolls can cross this river. So might have side towards sea wrecked. Could go further down where its ocean only. I suspect trolls can wade around any obstacle I place. May go inland a bit for my main base. Enough so moat is between base and ocean. Then I maybe only lose the dock portion, or can kill them while they attack that.