Istanbul (/ˌɪstænˈbʊl/ IST-an-BUUL, US also /ˈɪstænbʊl/ IST-an-buul; Turkish: İstanbul [isˈtanbuɫ]), formerly known as Constantinople (Greek: Κωνσταντινούπολις; Latin: Constantinopolis), is the largest city in Turkey, serving as the country's economic, cultural and historic hub. The city straddles the Bosporus strait, lying in both Europe and Asia, and has a population of over 15 million residents, comprising 19% of the population of Turkey. Istanbul is the most populous European city, and the world's 15th-largest city.