Istanbul is the largest city in Turkey and one of the major cities of the world. The population of Istanbul is officialy 15,1 million by the end of 2017, but in fact it has passed 17 million today which means that Istanbul is larger than 177 countries in the world in terms of population. The city was always important and big since the Byzantine and Ottoman periods but its dramatic growth started in the 1950's parallel to Turkey's rapid industrialization. A huge immigration began from the countryside to this most industrialized city of Turkey which still continues at the present time.
The economic potential of Istanbul is huge, it has 38% of Turkey's total industrial output and 40% of total taxes collected in the country are originated from here. Also, an approximate of 57% of national export and 60% of national import is made from Istanbul. The city has 30% of total commercial firms of Turkey, thus making Istanbul Chamber of Commerce (ITO) and Istanbul Chamber of Industry (ISO) as one of the biggest trade chambers in the world.
Therefore, Istanbul attracts many multi-national companies, international banks, offices, shops and brand names etc. The city has several business centers for offices and bank branches in all of its districts. There are 3 major shipping ports, 4 Free Trade Zones, 2 International Airports and the third one is being built nowadays. Istanbul is getting every year a larger share of international trade for various reasons, especially for being a natural bridge between East and West.