I'm not a fisherman, but while living in Michigan's Upper Peninsula a friend of mine living in the western U.P. liked walleye fishing at Lake Gogebic just east of Ironwood, MI. There is a large state park on the lake and there are private campgrounds in the area (check Wakefield, Bessemer, & Ironwood on RV Park Reviews.com).
Just north of there is the Porcupine Mountains State Park. It's a huge park with lots of hiking trails and beautiful scenery. I especially like the trails on either side of the Presque Isle River at the south end of the park.
This area is right across the border from Wisconsin and not far east of Minnesota so it's in your target area. Good luck with the fishing.
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