Our family had two rooms in the second floor of Big Cottage. Rooms were extremely charming but some details would need a small renovation (e.g. bathrooms). The biggest problem was the lack of air conditioning. When the temperature was +31 degrees outside, it was +27 degrees Celsius inside. Otherwise sleep quality was very good. Rooms were very quiet (except some creaks of old wooden floors).
The manor museum is the most beautiful interior in Finland, I think. There are hand-painted l'oeil paintings and also painted scenery wallpapers there. Figured parquets are made of walnut tree, birch, oak and ash. The sculpture named Diana in the floor lobby is extremely beautiful. Remember to walk in the park, too. It is quite big (22 hectares) and very beautiful. The architecture of the park is from the year 1787. There are oaks from the 15th century and many beautiful sculptures (genuine scultures or old replicas of still older sculptures) there. There are also the very nice Waterlily Trail and the Temple in the park. Totally there are 40 individually designed rooms with 70 beds in the hotel. All rooms seem to be very charming. It was very relaxing to walk in the park and to swim in the river. There isn't any sandy beach there but there are two very good piers from which you can go swimming. The better one is in front of Orangerie. Water was very clean and warm. However, it is very deep there and so it isn't a good place for small children. The restaurant of the hotel (named Linnankrouvi) is extremely good. You can taste award-winning Scandinavian food made from local, fresh and ecological ingredients there. Read my separate review of Mustion Linna restaurant, please. We had a very nice dinner in the restaurant. Also the breakfast was very good. The breakfast isn't as abundant as in many other hotels but again all ingredients are high quality and fresh. They even offered buckthorn juice. Very delicious!