This is my absolute favorite Hill Climbing Route. It begins in Alma, Wisconsin and goes through some stunning climbs along the bluffs of the Mississippi River. The ride starts with a 2 mile climb at about 6-10% and just goes on from there. There are several double digit grades on this route along with the descent of the famous "Alligator Slide" featured in Bicycling Magazine.
Services are VERY few and far between on this route. I've been known to knock on someone's door out of desperation.