Iles Purpuraires are a set of small islands off the western coast of Morocco at the bay located at Essaouira, the largest of which is Mogador Island. These islands were settled in antiquity by the Phoenicians, chiefly to exploit certain marine resources and as a promontory fort. (Hogan, 2007) Roman occupation of western Morocco beginning in the 2nd century BC continued the use of the islets, principally for manufacture of a royal blue dye from certain marine organisms.