US-52 — Upper Iowa River Driftless Corridor

US Route 52 runs 174 miles north-south through northeast Iowa, from the Mississippi River near Sabula north to the Minnesota border near Burr Oak. The route is wholly within the Driftless Area for its northern stretch, crossing Jackson, Dubuque, Clayton, Allamakee, and Winneshiek counties. Near Decorah — where it crosses Iowa Highway 9 and the Upper Iowa River adjacent to Luther College's limestone-cliff campus — the road rises and falls hundreds of feet through river valleys and past forested bluffs. The northern segment overlaps the River Bluffs Scenic Byway and Driftless Area Scenic Byway. The loop from Decorah south via US-52 to IA-136, connecting with the Grant Wood Scenic Byway corridor, is a well-established northeast Iowa motorcycle day ride.