expert of Geography and cartography in medieval Islam, usually named it as Persian sea a vast sea from vak vak island (including Thailand coast and Andaman sea to the west Basra bay and to the red sea. some of them called all body of water in north Indian ocean as the Persian sea (Bahre Fars) and the south part as Erythraean sea European geographers and travelers, also Differentiated between Persian sea and Persian gulf and Indian ocean.