The apartment is really well located: in a quiet district but it is just 10 minutes walking distance from St. Stephan platz.. The apartment is brand new. It is cosy, warm and super clean, perfect for a couple. The only problem we had was a neighbour which started playing the violincello at 7.30 in the morning, but this has nothing to do with the place itself. Katharina is very kind and easy reachable for any problem you may have.
Place highly recommended!