Heading out of St. Paul along the industrialized Mississippi riverbanks, the GRR crosses the St. Croix River at Prescott, Wisconsin, and wends south on Hwy-35 across a portion of the glacial plain whose rolling hills, sown in corn, account for an important part of the nation’s breadbasket. The fertile soil here, as throughout the Midwestern grain belt, is a product of drift: pulverized soil left by mile-thick ice sheets scouring the ancient sediments of an inland sea for about two million years. Farther south, however, the GRR enters a very different landscape, known as the Driftless Region, an area of limestone bluffs and rocky uplands bypassed by all that rototilling glaciation. Stretching south into Illinois, and covering an area four times the size of Connecticut, the Driftless Region affords dramatic views, wildlife habitat, and a setting for one of the more painful episodes in Native American history, the devastating Black Hawk War.
The GRR follows two-lane Hwy-35 from Prescott south for nearly 100 miles, staying within closer view of the Mississippi for longer stretches than almost anywhere else on the route.