Poilvache Castle is a ruined medieval castle in the Walloon municipality of Yvoir, overlooking the village of Houx from a clifftop on the river Meuse.
The present ruins date from the 15th century, although there has been a fortification on the site since the time of Charlemagne. The Liégeois town of Poilvache, a thriving walled town, protected by a castle, with a prosperous economy and its own mint, and allied to Duke Philippe the Good, virtually ceased to exist following its 1430 siege by the rebellious Prince-Bishop of Liège, Jean de Heynsbergh, and an estimated army of 30,000 Liégeois, Dinantais and Hutois. The Dinantais besiege Montaigle Castle in 1465 for the same reasons but Montaigle was destroyed in the 16th century by the army of Henri II of France.
From the top of these rocks it is possible to see the isle in the river where the German army and its armoured divisions crossed (in the North of the isle), the river Meuse on 13 May 1940.
References:The Château de Foix dominates the town of Foix. An important tourist site, it is known as a centre of the Cathars. Built on an older 7th-century fortification, the castle is known from 987. In 1002, it was mentioned in the will of Roger I, Count of Carcassonne, who bequeathed the fortress to his youngest child, Bernard. In effect, the family ruling over the region were installed here which allowed them to control access to the upper Ariège valley and to keep surveillance from this strategic point over the lower land, protected behind impregnable walls.
In 1034, the castle became capital of the County of Foix and played a decisive role in medieval military history. During the two following centuries, the castle was home to Counts with shining personalities who became the soul of the Occitan resistance during the crusade against the Albigensians.