http://www.lonelyplanet.com/worldguide/destinations/europe/turkey/istanbul/This link about is Istanbuls Geographical position. Istanbul is in between Asia and Europe. Istanbul is conquered by Fatih Sultan Mehmet in 1455 the Ottoman empire emperor. Than Fatih changed its name from Costantinople to Istanbul. And made it the capital of Ottoman empire. Istanbul's geographical and strategic position is very important to the world Istanbul connects Asia to Europe , and Europe to Balkans with the water ways.
http://www.mymerhaba.com/en/main/content.asp_Q_id_E_309In this link you can learn about the palaces and the most precious world wide known historical monuments. There are very precious palaces which remains under the control of Turkish government and they are restored once in a while. Some of them made museums and they good income.
http://www.turkeytravelplanner.com/Maps/ist_metro_map.htmlIn this link you can view Istanbuls towns and the cities that shows touristic places that you can visit such as bazaars, palaces, museums. Manny tours held by Turkish government and there are sponsors for them. They will take tourists to Grand Bazaar, museums, and some other shopping places.