Beaufort Castle consists of the ruins of the medieval fortress and an adjacent Renaissance château. It probably originates from the 11th century when a small square-shaped fortress was built on a large rock protected by a moat and a second wall above the valley. A reference from 1192 indicates that Wauthtier de Wiltz et Beaufort was its first lord. During the first half of the 12th century, a keep was added and the gate was moved and enlarged. In 1348, the property came into the hands of the House of Orley after Adelaide of Beaufort married William of Orley. The Lords of Orley made significant extensions overlooking the valley. In 1477, Maximilian of Austria transferred the castle to Johann Bayer von Boppard after Johann von Orley-Beaufort committed a breach in trust. In 1539, Bernard von Velbrück became Lord of Beaufort through marriage and added the large Renaissance wing with cross-framed windows on top of the medieval walls.
The castle then came into the hands of Gaspard de Heu who had married Velbrück's granddaughter. A partisan of the Dutch resistance and the House of Orange, de Heu was captured by the Spaniards, accused of heresy and treason, and publicly executed in Luxembourg's fish market in 1593. Philip II of Spain confiscated the property and entrusted it to Peter Ernst Graf von Mansfeld, the governor of Luxembourg. Through marriage, the castle became the property of Henri de Chalon and then Gaspard du Bost-Moulin who had to sell it after being ruined by the Thirty Years War. Acting on behalf of the Spanish king, Johann Baron von Beck, governor of Luxembourg, bought most of the property in 1639. He initiated the construction of the Renaissance castle in 1643 but after he died of injuries from the Battle of Lens in 1648, the work was completed by his son in 1649.
After various changes in ownership including Pierre de Coumont (1774) and Jean Théodore Baron de Tornaco-Vervoy (1781), the castle was abandoned, fell into disrepair and at the beginning of the 19th century was even used as a quarry. In 1850, it was listed by the State as a national monument. In 1893, the new owner Henri Even restored the new building and, in 1928, Edmond Linkels cleared the rubble away and opened the medieval castle to visitors. In 1981, the property was acquired by the State.
The ruins of the medieval castle are open to visitors in summer season.
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.