Thanks, I’ll use that if I get a chance to do the reminder of the route.
I took a wrong turn in Eiken, which isn’t directly next to the river, and didn’t notice my mistake until I’d already exhausted myself. The nice scenery was a pleasant but unfortunate distraction.
(Also, it's well-signposted, and in any case the whole point of the route is to follow the biggest river in Europe, you don't need a lot of navigational aids).