The town of Moulay Idriss, or Moulay Idriss Zerhoune, is spread over two hills at the base of Mount Zerhoun, approximately 3.5 km/2 miles from Volubilis.  The town was settle by Idris I, founder of the Idrisid dynasty settled when he came to Morocco in 789/172 AH.  Numerous sacred sites are located there, the most important of which is the mausoleum of Idris I, just off the main square.  Because of it, the village is a national pilgrimage site, and until 2005 non-Muslims were not allowed in the village after sunset. 

Sources:
Barrucand, Marianne. "Idrisid." Grove Art Online. Oxford Art Online. Oxford University Press, accessed January 16, 2014, http://www.oxfordartonline.com/subscriber/article/grove/art/T039849

Touri, Abelaziz. "Apercu Historique." In Le Maroc andalou: à la découverte d'un art de vivre, 36-37. Casablanca:  Editions Eddif ;  Aix-en-Provence:  Edisud, 2000.