Thierry Castle, locally known as Château de Thierry, lies in the woods west of the of Falmignoul, on a high rocky plateau overlooking the Meuse river valley, in the province of Namur in the Wallonia region in Belgium.
The first castle here was owned by a Thierry, Lord of Faing. With his castle he protected the Waulsort abbey on the other bank of the river. From this first castle nothing remains.
The oldest parts of the present ruin date back to just before 1262 which was proved by archeological excavations. This castle was probably built by Gilles de Rochefort and his wife Héluide de Faing.
Their reason to call the castle "Thierry" was probably three-fold; she was the rich heir of her father Thierry de Faing, who had died in 1218. Gilles had become Lord of Rochefort and Walcourt thanks to his father, also named Thierry, who had handed him al his rights when leaving for a crusade and the son of Gilles and Héluide was called Thierry.
In 1221 Héluide had left the protection of the abbeys of Waulsort and Hastière to her husband. In later years the castle and the lands it protected passed through the hands of 4 other families; the Looze de Agimonts, the Boulans, the Brandebourgs and the Spontins de Freyr.
Thierry Castle never became the main residence of either family. They just used it to profit from the abbeys they had to protect and to rob merchants going down the Meuse river.
The ruins are fenced off so access is prohibited. But the walk to the ruin alone, over a forest trail, is worth the trip. Inside there are a well, several stretches of cobblestone floors and remnants of an oven. There is also a great view over the river valley.