This was probably the worst hotel I've ever stayed at, and I spend at least 1-2 nights per week in a hotel.
The service is atrocious. The staff do not speak any English - which is fine, but they made no effort to communicate with us. When we first checked in, they kept scrolling past our reservation and ignoring us when we told them they had missed us. Instead, they tried to insist we didn't have a reservation. Once we got this sorted out, they neglected to tell us that the whole hotel would be locked 9PM. They didn't give us a night key, so we almost got locked out - luckily my boyfriend found another customer who spoke both German and English, and he was able to translate. The staff then acted extremely annoyed at having to give us a house key. The best part is - when we tried to leave in the morning, the hotel was locked FROM THE INSIDE. So not only did they almost lock us out, they also almost LOCKED US IN. We tried asking staff for help multiple times, but they ignored us while pounding beers at the restaurant bar.
The rooms are run down. We had handles missing on furniture, sheets of questionable cleanliness, and windows that let bright light in due to sheer curtains. The walls were so thin that you could hear anything your neighbors were saying. The hotel is also a meat factory, so it reeks. On top of this, there is construction in Hallstatt so it takes 20-30 min to get there during daytime traffic, not 5.
In short... avoid this place.