I have to confess, I was aware of Igloo for a year or more before I set foot inside. Really, the only reason I finally set food inside was that a friend had a craving for soft-serve ice cream.
I will say now that, if you are in Gloucester, you really need to stop in at Igloo. Yes, it has only soft-serve ice cream. Yes, children are its primary audience. But it also has pretty spectacular, fab-'60s decor; a high number of adults sitting on stools at the counter; and a dense, creamy, winning product as its ice cream. Really good stuff.