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 Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.