Willow River State Park, near Hudson, Wisconsin

Under an hour's drive from Minneapolis and Saint Paul is this lovely park in our neighboring state of Wisconsin. Excellent day trip!
The falls hike is about four miles round trip, not overly strenuous. Beautiful falls area where you can get in the water and even go behind the falls. Family friendly, but of course keep a careful eye on children in or near water. Rocks can be slippery.
Optional stair climb to an overlook.