This is the best place to stay in Istanbul. I've been to Istanbul three times and have always stayed at Marmara Guesthouse. The location is the best in the central historic district. Very safe area, very walkable area and very close to the main historic and cultural sights such as the Hagia Sophia, Blue Mosque and Topkapi palace. The guesthouse is very comfortable, beautiful view from the terrace. The rooms are very well equipped, very comfortable beds. Everything is extremely clean. Rooms have a safe and mini bar which is excellent. The breakfast is delicious as well as the coffee. I love to have breakfast and drink coffee on the terrace in the morning and see the water and the seagulls. It is an unforgettable experience. The guesthouse has everything you need and there is ample attention to detail such as the breakfast, coffee, slippers, comfortable bed, clean place, all accessories in the bathroom. The staff is extremely helpful. It was also extremely convenient to be able to book tours and airport transfers with them. I give marmara 200% because they are beyond excellent!