Years ago, in Germany, we were required to transit IFR (DOM - BOTTROP - LIMA?) between Gutersloh and the “Clutch” airfields (Wildenrath, Laarbruch and Bruggen).
It was quite tricky, bearing in mind that the route included an NDB and our aircraft didn’t have a receiver (or, for that matter, Mode C, only a single non Y channel VOR and a separate DME). We used to get marked out of ten for our DR by some Clutch Radar controllers because it didn’t take them long to suss it out that we had to bluff our way along.