The Governor of Wisconsin has declared August as "Caving Month." Here is a map of one of their caves:
http://www.uwec.edu/jolhm/Cave2007/TeamC/TeamC/CrystalCave/Crystal%20Cave%20Map.jpg I don't know anything about the caves up there, but I have been on a very short but fun rafting trip on the river of the north border of the state, just a few miles south of Iron River, in the upper peninsula of Michigan. http://farm4.staticflickr.com/3494/3975550583_05ac3a950b.jpg
