Why Marrakech Is Red and Fez Is Ochre
Two imperial cities, one element in the ground — and the difference between a red city and an ochre one turns out to be half geology, half planning law.
Marrakech shows you the iron in its earth; Fez veils the same iron under lime. What makes each city relentlessly one colour, though, isn't the ground — it's what the twentieth century did to it.