It’s on the Wednesday morning in Granada that it happens, proper confirmation that I am old. Here I am, fresh from walking the Caminito del Rey, sporting a T-shirt from my travels, boarding a shuttle bus from city centre to the Alhambra and feeling full of the joie de vivre which travelling the world brings, when some guy stands up to offer me his seat. This is the first time anywhere in the world that this has happened to me. I must look so old now that it’s obligatory for someone to offer me their seat. I am suddenly and undeniably an old git. Inside I’m cursing him and wanting…