Fez is the one Moroccan city that resists being done in a day, and the writing about it splits neatly into people who have spent real time inside the medina and people who have not. These five are the first kind. Between them: the tanneries and what they actually smell like, the artisans working the same trades in the same lanes, the Sacred Music Festival, mlaoui from a neighbourhood vendor at seven in the morning, and how not to get comprehensively lost.
The View from Fez has been posting since 2005 and is still the best English-language blog in Morocco. Read it for a week before you go and you'll arrive knowing what's on.