Free Nav teaching exercise in Wales with my regular student. He was a bigger bullpooper than me and convinced me that he was correct and I was not. Turns out he wasn't and the result was we were completely and utterly lost in the one bit of Wales I didn't know. Nothing other to do than head west, find the coast, fly North until we found something we could identify. Aberystwyth it turned out.
The free Nav teaching exercise was all about being lost for most of the trip.