Another WI State Park along Lake Michigan is Point Beach just north of Manitowoc in Two Rivers. Nice hiking/walking trails. Manitowoc has a Maritime Museum that is very interesting.
Harrington Beach SP is closest to Milwaukee of everything mentioned here. Nice hiking/walking trails, especially the one around Quarry Lake.
Kettle Moraine SP, Ottawa Lake, is between Milwaukee and Madison but furthest from Lake Michigan. Only one walking/hiking trail with direct access from campground.
We've been to all 3 several times and enjoy them all.
