A visit to Istanbul is Not harking back to the times of the Eastern Roman Empire, Then Byzantium, the Ottoman Empire, a clash and blending of cultures as in very FEW cities in the world That gives. As to What to see in Istanbul is Nothing Better to take a walking tour of the main historical sites of Istanbul.
The guided tours start at your hotel around 13:00 where the guide will lift passes, the tour begins with a visit to Ayasofya (Hagia Sophia), followed by stone Milion visits, the Basilica (Sunken Palace), the Cisterna (Yerebatan Sarn?c? Saray), the imperial tombs of the Ottomans in Divan Yolu, the Column Quemada (Cemberlitas) and Cemberlitas Hamam (Turkish bath), and the Grand Bazaar (Kapali Carsi).
The tour ends about 16:30 at the Grand Bazaar, which gives you time to stroll through the store on your own if you prefer or return to hotel. But the Grand Bazaar, lives up to its name and attractions are such that no doubt will take all afternoon along it.
For lunch, if you decide to take the morning tour the tour stops at the famous Sultanahmet Lale Restaurant. The Lale is a good choice because it has a good selection of ready food, free wifi, wine and beer.
You choose what you want for lunch, or you can go to another site. Always good to ask the locals to do in Istanbul, as they are the best guides to see these forgotten and little known corner of this ancient city.