Collapsed wall

Unfortunatley each year we tend to find one or more of our terrace walls has succumbed to gravity and rain. This one formed part of our turning circle and so needs to be repaired. With ageing knees it is not something I Iook forward to. 
The hard bit is starting the process off. Once the first layer of stones is laid, the work is not too bad but digging thr rubble out before one can start is somewhat depressing.
This one is not helped by as huge lump of rock overhanging the break held in place by a weedy bit of cement.