Istanbul, historically known as Byzantium and Constantinople is the largest city of Turkey. Istanbul metropolitan province had 13.26 million people living in it which is 18% of Turkey’s population and the 3rd largest metropolitan area in Europe (including the Asian side of the city) after London and Moscow. Istanbul is a mega city, as well as the cultural, economic, and financial center of Turkey. It is located on the Bosphorus Strait and encompasses the natural harbour known as the Golden Horn, in the northwest of the country. It extends both on the European (Thrace) and on the Asian (Anatolia) sides of the Bosphorus, and is thereby the only metropolis in the world that is situated on two continents.