Ibrahim ozan B: "When you stop at the Hippodrome Sq. You can see Egypt, Rome, Byzantine an Ottomans just changing the your heads position.
Hagia Sophia, Sultanahmet Mosque, Basilica of Yerebatan, Archeology Museum, Topkapi Museum, Obelisk and Hippodrome are the other closest points of interests.
Please try the famous meatballs of Sultanahmet.
Spending one day in Sultanahmet will not be enough to see everything around."