I once made a mayday call. I was going down and knew that nobody knew where I was within 20-30 miles, phone coverage was poor and this was before the days of phone tracking. I landed successfully on a very steep rock covered hill and it was only sheer luck that I didn't roll back down the hill to the certain destruction of the aircraft and possibly my jumping out if I was still able to.
Nobody heard the mayday call and luckily I was able to walk to a house to find out a location to get picked up from.