Hiking the complete Sufi Trail is not such an easy task but to complete it all alone and you are 70+ is to put it mildly pretty extraordinary. I asked David what were his plans after his pilgrim journeys.

To answer your question what next. 
Three years ago I set out to walk the three great Christian medieval pilgrimages, to Santiago de Compostela, Rome and Jerusalem. I was 74 years of age in 2017 when I started out to Santiago having never walked a long-distance trail before, in 2018 I completed Canterbury to Rome and, last year I completed Rome to Jerusalem. In total over 6000 kilometres all on foot. It has been an extraordinary three years, meeting wonderful people and exploring extraordinary landscapes, and to reach Jerusalem was momentous and for me the end of the trail. I will continue walking but nothing on the scale of the past three years. Perhaps when I followed the Sufi Trail, maybe, I was the oldest so far?
You have done an extraordinary job with the Sufi Trail, so good luck with its continuing progress.