Complex sentence: By the 11th century Volubilis had been abandoned with the seat of power relocated to Fes and much of the local population had been transferred to the new town of Moulay Idriss Zerhoun, about from Volubilis.
Split into simpler sentences: By the 11th century Volubilis had been abandoned with the seat of power relocated to Fes. Much of the local population was transferred to the new town of Moulay Idriss Zerhoun, about from Volubilis.