I used to keep a local city map folded up this way in my backpack just in case I needed to go somewhere I hadn't been before or got lost biking, or somesuch, it was super useful.

However, the advent of smartphones has made that sort of thing less useful. And for serious wilderness navigation this kind of map folding is very unhelpful since maps tend to be big and it helps to keep the map partially folded so you can focus on one area.