The only European country which kind of gets near that is France
Dunno, in
germany everything above 2500ft AGL (lower around controlled airports) is class E and everything above FL100 is C, FL130 at the alps. Class A or B isn't used though. That's still enough to enable IFR services outside of any kind of airways. The old corridor system was used within eastern germany of course, but that was over 20 years ago. Anyway, the airway structure is so dense that one is always around some airway, but usually not on it since one flies on some kind of direct clearance.