Illinois north of Chicago

Hi all,

Ill be staying north of Chicago next week.
The pool at my hotel si going to open.

First thing, since I cant go nude there (unless no one sees me), is it allowed to swim with a thong (covering everything on the front of course) ?

Another question, what can you do nude there ?
Any bath house where entirely nude ?
I would love to enjoy some relaxing time in the evening. Not far from Chicago, so I can drive there too.

Thank you very much for all the advice.