There is Bosphorus tour which is organised by IDO( Istanbul's official ship service).It starts from Eminonu and ends at Anadolu Kavagi.This tour is made during specific season(from spring to winter).You will travel with the classical ship through Bosphorus;from Eminonu and ship goes to the ports of Besiktas, Kanlica,Yenikoy, Sariyer, Rumeli Kavagi and Anadolu Kavagi.You can have 2 or 3 hours at Anadolu Kavagi;eating fish at the restaurants on the seashore,and you can visit the fortress on the top of Anadolu Kavagi and watch the beautiful scenary of Marmara Sea and Black Sea.There are small souverier shops,that you can buy some small gifts.And you can go back to Eminonu with the next ship.During your travel you will see the luxurious mansions near Bosphorus.