Stayed at the Adina for 2 nights. We were a group of 3 and were given a room on 15th floor. Amazing views, room beautiful, lovely details such as heated mirror in bathroom, really nice toiletries, even a dishwasher and washing machine if you were staying for an extended period. We had a small issue with camp bed, was unsteady, we reported this to reception and it was replaced asap. Staff very friendly and helpful. Nice lobby and bar area, we had lunch on arrival, enormous food portions. The location of this hotel is really excellent, we were in a room at front of hotel so had wonderful river views. Also only a 5-10 minute walk to train station, and the same to city centre in opposite direction. Also for any opera fans its a 1 minute walk to the opera house. If returning to Frankfurt I would book this hotel immediately. As an aside if visiting Frankfurt and have a little time I would recommend paying a visit to Heidelberg, about 1 and a half hours by train from Frankfurt, really convenient service and very reasonably priced. Heidelberg is beautiful and a visit by cable car to the castle is a must, just 6euro.