The historical castle has been transformed into a hypermodern hotel, the architect really did a marvelous job. The castle is at the lakeside, offering stunning views. The rooms are perfect, with all modern comfort. Exceptional bathroom, with walk in shower.
On the downside, staff at the restaurant could be a bit friendlier (they walk around as if they would rather do something else than being a waiter). Beware also of the parking: it is quite small, and if it is full, you have to park in a public parking lot, at a short distance (even if you explicitly reserved a parking space beforehand).
There is also a small swimming pool, nice and refreshing. Swiss punctuality is not what it used to be though, as it was not open at 8 am, as indicated.