A wonderful hotel close to Checkpoint Charlie and the Currywurst museum. This hotel used to be the headquarters for the secret police during the time of the DDR, but you wouldn't know it by how it looks now. The rooms are very modern and clean. The green theme is an interesting choice, but I think it's part of the Gat Hotels schtick. The reception was very helpful when we arrived, giving us tips on where to go and telling us about monuments that weren't in our guide book.
The location of the hotel is perfect, as it's right next to many sights and also minutes from the subway.