This town house built in 1777 for Marie-Josèphe Sandelin, Countess of Fruges stands between a courtyard and garden. The itinerary shows off the museum's rich collections, including swords and firearms from the 12C to 17C, medieval vestiges, religious art and ceramics. It leads from the cellars to the first floor, through three adjoining drawing rooms with period wood panelling, Louis XV furnishings and paintings from the 17C to 19C (Nattier, Boilly, Flemish Primitives).