 The play had originally been filmed with actor Ray McAnally (qv)  playing the lead part of Alan Holly. He died just before completion  so the BBC started from scratch with Joss Ackland (qv). The second  time around, they decided to film the walk in reverse order,  starting with the John OGroats scenes (the end of Alans walk) and  ending with the Lands End scenes (the beginning of the walk).