LONG before GPS actually… Motorcyclist riding long distances either for work, leisure or (originally) military purposes used a system called a “Road Book”  which allowed you to ride without continually stopping to check maps. Basically a long scroll of paper that is manually, (or in the more sophisticated versions, mechanically – connected to the odometer) wound to show the distances between established reference points, I reckon this would be a pretty useful, if not a completely accurate/reliable tool. I like the wrist worn version too.