Istanbul formerly known as Constantinople 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.

Hagia Sophia, Leander’s Tower, Galata Tower, Yedikule Fortress, Topkapi Palace, The Obelisk of Theodosius, Bosporus strait and mosque minarets are shown in the illustration.