Bailli Castle, locally known as Maison du Bailli, lies on a hill in the town of Gembloux, north east of the city of Charleroi, in the province of Namur in the Wallonia region in Belgium.
Well, this not truly a castle but I have added it anyway. It was built on the foundation of an older building which was, as its name indicates, the residence or workplace of the town's baillif who was appointed by the abbot-count. Of that former building nothing remains but two cellars, dating back to the 12th and 13th century, underneath the present building.
In 1589 the abbey gave up its property and sold it to the Salmier family, who built the present castle. At that time the castle was a square building with one, circular, corner tower.
In 1937 it was enlarged on the west side with a modern tower. Other modifications had already been made to the building during the 18th and 19th century. At present the castle is used as a city hall.
The castle was built next to the old town ramparts. So at the edge of the castle garden stands the medieval Tour du Guet; the southern tower of the old town's enclosure.