Depends of course how neat you want it etc and how accurate/uptodate.
IF lucky one can still find supplies of all folded maps, dated some 3-4 yrs ago now, in some DB-travelcentres and I think these aim to advertise walking/wander areas or the like. Which also means some areas have ads for that over the map.
I have a few @home, but am now faraway, so cannot check details-I use one to have all lines Ie ´done´ run over inked. And another one for regional buses-many done last yr with the 9€ monthlies.
If having higher standard wished, as always: try the german forum , bro/sis of this: drehscheibe-online.de. I think there is also a 2nd hand on-sale section, text is of course all german.
Remember also from a simply google/maps search that several through the yrs were shown then.