Start the day with a visit to Hagia Sophia, the most influential church of Byzantium, it still stands today as one of the world's greatest architectural marvels. Then visit the Blue Mosque, another of the world's most important religious buildings. Built in the 16th century the mosque is unique for its 6 minarets and celestial interior decorated with the famous blue tiles.
Next, visit the Hippodrome, scene of chariot races. Obelisk of Theodosius, the Serpentine Column and the Column of Constantine. The grand Topkapi Palace, residence of Ottoman Sultan's from the 15th to the 19th century. Overnight in Istanbul.