Turkey has the city of Istanbul, which lies on both Europe and Asia. The Bosporus Strait separates the city’s European and Asian sides and connects the Black Sea with the Sea of Marmara. Istanbul is the world’s most populous city spanning two continents.
The city was founded as Byzantium, became Constantinople under the Roman and Byzantine empires, and was renamed Istanbul in common official usage after the establishment of the Turkish Republic. Constantinople was captured by the Ottoman Empire in 1453, an event traditionally used to mark the end of the Byzantine Empire.
Istanbul is Turkey’s largest city and its cultural and economic centre, although Ankara has been the national capital since 1923. The city’s historic peninsula contains landmarks such as Hagia Sophia, the Blue Mosque and Topkapı Palace. Istanbul’s transcontinental location has shaped its role in trade and history.