The place is north to Septimus(spelling?)post.It has a friendly frost atronach inside.I play that game one year now and its the first time i encounter that place.Which makes me wonder what other things i havent found....
And a question.Has anyone explored underwater Skyrim?I have found those ships in winterhold but i havent explored elsewhere.Considering how vast is the underwater section of Skyrim i am 100% convinced that Beth has some "hidden" secrets down there(like Fin glim on Oblivion or Easter eggs or even unmarked underwater caves).Still the place is so huge that i would spent hours to explore it....