My wife and I stayed at Ada for three nights and had a wonderful experience. The hotel has a fantastic location within very close walking distance to the major tourist sights, Blue Mosque, St. Sophia etc.
When we arrived we they upgraded our room free of charge and it had a lovely view of the sea. The staff were always extremely helpful in helping us find a hammam, they bought tickets to various tours for us and were always extremely friendly. Our first morning we woke up after breakfast was finished but they insisted that they still fix us something (the rooftop where you eat is fantastic.)
The only odd thing that happened was that the cost per night was in Euros and not Lira so the stay was a bit more expensive than we thought it would be. However, we noticed this in many places in Istanbul. We quickly learned to ask how whether things were priced in Euros or Lira.
But again, it was a great stay in a wonderful room with wonderful service.
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