Housed in a 1762 building are beautifully restored rooms, dressed in aristocratic styles from the 18th and 19th century. As interesting as the trompe l'oeil tables and hand-painted furnishings are examples of aristocratic clothing...the dresses in particular are feats of engineering.
It's good value to buy a joint ticket (adult/child €6/3) that also grants access to the adjoining Museum of City History.