About 6 years after I moved to London I was on holiday in Weymouth and saw 'DC' who I hadn't seen since we were at school together. He now had long hair and a substantial beard.
Even though we used to walk home from school together everyday, it took me a while to recognise him. What eventually convinced me it was him was the distinctive way he scratched the side of his nose, a bit like a rabbit. I didn't make myself known to him. My home town was the past and I was trying to turn my back to it.