This is the USS Iowa's gunnery tower, from which it's main guns' fire is controlled. It's located behind the aft superstructure, and is VERY heavily-armored.

It's placement on the ship isn't a hindrance to gunnery directed straight ahead over the forecastle, because this isn't done --- the Iowa class Battleships fire only over their broadsides, as with most Battleships.


I hope that it's open to the public the next time I visit the Iowa!