I don't even want to know what kind of phone you have if unfolding a map, tracing and memorizing your route, and folding it back up is quicker than a GPS lock. On any phone I've had since 2009, GPS lock has been instant.

All I needed to do was look up the number of a junction. The rest of the route was pretty straightforward. And it was not a foldable map, just a big book. Way less faff than getting the phone out of my pocket, unlocking the screen farting about looking for a map app, waiting for it to load then get a GPS lock.