What’s the thing with the windows..
Looks like a fortification or sumpin.
That is Fort Gorges, Sissy..
Go here for more info:
http://www.smccme.edu/docs.php?section=5&navid=2&levelfour=166&docid=79
Ms.B
Yes its an old Forte. The coast is crawling with them.
That one is from colonial days but there are many anti submarine lookouts from WWII as well