Check it. The Mississippi River carved its way through soluble limestone and dolomite with assistance from periodic glacial forces. Today's result is a broad valley between Iowa, Wisconsin and Illinois in the upper segment of America's river.
This view looks east from atop the Balltown ridge (north of Dubuque) and overlooks farmland, the Mississippi river and the cliffs of Wisconsin - although just the farmland is visible here. The 2011 corn crop looks in fine shape from this advantage point.
Another farm visible from this lookout is a grain operation and cattle lot. All of this great scenery can be experienced at Balltown, Iowa. While there be sure to stop at what was Iowa's oldest restaurant - Breitbach's Country Dining. It was destroyed twice in separate fires but came back each time to again serve German-style food. Our captive people viewing the valley (above) had just finished their Sunday dinner and visited the overlook, a block from Breitbach's. Know that.