Mersch Castle is one of the castles belonging to the so-called Valley of the Seven Castles. The castle was built in the 13th century by Theodoric, a knight in the service of Countess Ermesinde of Luxembourg. It was captured and burnt down by the Burgundians. In 1574, Paul von der Veltz transformed the building into a comfortable castle in the Renaissance style. The keep had large windows and the property was surrounded by a protective wall with seven towers. Finely vaulted ceilings were erected over the rooms on the ground floor and the first floor. The Knights' Hall on the second floor has a magnificent chimney. The arms of 16 noblemen decorated the walls. In 1603, the castle was again destroyed by the Dutch. In 1635, during the Thirty Years' War, the castle and the village were left in a sorry state. However, around 1700, it was once again repaired, this time by Johann-Friedrich von Elter who rebuilt the gate and appended his coat of arms. The chapel was restored in 1717 by von Elter. The altar bears the arms of the castle's heiress, Charlotte von Elter.
In 1898, the Sonnenberg-Reinach family sold the castle to a businessman called Schwartz-Hallinger. In 1930, restoration work was carried out by the owner M. Uhres. In 1938, a youth hostel was housed in a new building adjacent to the castle. From 1957, the commune acquired the building but sold it to the State of Luxembourg in 1960. As a result of an exchange agreement, the commune finally regained ownership in 1988 and undertook substantial renovation work for the needs of itse administrative services which now occupy the building.
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.