The talk about BO Tower leads me to ask, what towers are still standing in the upper peninsula? A tower didn't necessarily have to be in a tower like building, it just needed to control something out there. But I will exclude yard towers from this question.
In use still:
None
Standing but not used for tower functions:
???
So what is left out there? I will post a thread in the other(lower peninsula) forum for towers in troll land.