We stayed at the Bristol for two nights and what a wonderful experience. The hotel is a fine example of a very well cared for 'grande lady' of European hotels. From our perspective it really is the jewel in crown of Marriott's Vienna hotels (Lifetime Titanium member). Not sure when last renovated but all facilities and features very up to modern standards. Bed super comfortable, hi-tech air con control, and perfect bathroom and shower (separate bathtub if desired). Located right next to Vienna Opera House.
Excellent full buffet breakfast, the best eggs Benedict, fresh whole avocados and self-serve champagne!
The entire staff totally professional yet very friendly.
We had drinks at the Bristol Bar, dinner at the hotel's restaurant and also had used their spa - all excellent.
We strongly recommend choosing the Hotel Bristol when in Vienna and well worth spending a bit more to stay there for true luxury..

We had previously stayed at the Hotel Bristol when we visited Vienna years ago, so we decided to stay there again when we returned to Vienna this time. The location is perfect. Right next to the beautiful Opera House and within easy walking distance to many sites.
The decor is very heavy, wood, but rich in history. So if you are looking for a contemporary or modern feel, this won't be the place for you.
We may have received an upgraded room because of our membership in the Marriott rewards program, because the room was large, but it had absolutely no view. Our windows looked out at an interior courtyard that was dark, metal, had ladders stored on it, and faced other rooms. Not exactly what you hope for when staying in a luxury hotel and reading the reviews of others who had small balconies overlooking beautiful views. We were given a box of chocolates and a bath bomb for our tub because we had no view. Didn't really make up for it though.
The service we received from the staff was top notch, especially in the dining room the night we ate there. So, mixed feelings about this hotel.

We had a wonderful four-night stay at the Bristol. It is so centrally located we could walk to everything. Our room on the 5th floor was large and comfortable, with a little sitting area and French doors that opened to a view of the Opera House across the street. The staff were very gracious. We enjoyed our breakfast each morning and had lunch at the restaurant one day - everything was delicious. Will definitely come back!