Thank you all!
If you follow that link there are quite a number of them. The first one is somewhere about 30-45 min north of Duluth, where the water was the coldest that I've experienced in Lake Superior, you could stay maybe 10 sec before the pain was too much.
Most of the Lake Superior shore is like that once you go west of Marquette/ Pictured Rocks. The Canadian side of it, the western part in particular, is quite wild.