Can I determine if my unit can be seen?

Question

Is there a way to determine if my units are still visible? Mostly in trying to set an embarkment trap, how far to keep destroyers off land

One more, do subs become invisible again after an attack?

Answer 1

There is no way to determine if your units can be seen. This makes scouting very important.

However, you can estimate distances based on common units statistics. In your case, since most land units have a vision range of 2, keeping your ships more than 2 hexes away can be enough. Just remember cultural borders grant vision (of their contained hexes + 1 hex away), too.