
Istanbul is Turkey's largest city, spread over both banks of the Bosphorus strait and so across Europe and Asia.
Founded as Byzantium and later the capital of the Roman, Byzantine and Ottoman empires as Constantinople, it keeps traces of all of them. The historic peninsula holds Hagia Sophia, the Blue Mosque, Topkapı Palace and the Grand Bazaar, while ferries cross the water to the Asian districts of Kadıköy and Üsküdar.