Hagia Sophia, basilica, later a mosque, now a museum, one of the greatest surviving examples of Byzantine architecture
Topkapi Palace, residence of the Ottoman Sultans
Blue Mosque, Istanbul’s only mosque with six minarets
Dolmabahce Palace, with european artistic influences
Grand Bazaar, one of the largest and oldest covered markets in the world
Chora Church, famous preserved galleries of Byzantine mosaics
Suleiman Mosque, huge dome and slim minarets
Istanbul Archaeological Museum, Alexander sarcophagus, Iznik tiles, Karaman Mihrab,  the Treaty of Kadesh…
And Basilica Cistern, Egytian Bazaar, Galata Tower, Princes’ Islands, Theodosian Walls…