Kärkna Abbey, now ruined, was a former Cistercian monastery in Estonia. The monastery was founded before 1233 by the Bishop of Dorpat, Hermann von Buxhoeveden, and settled by monks from Pforta Abbey, of the filiation of Morimond. An early destruction by heathen inhabitants of the district is mentioned in 1234. After attacks by Russian forces from the principality of Vladimir-Suzdal and the Novgorod Republic it was rebuilt in about 1240 as a fortress surrounded by a moat and a rectangular granite wall. In 1305 it was placed under Stolpe Abbey on the Peene in Pomerania, which had joined the Cistercian order the previous year. In August 1558 the monastery was destroyed at the beginning of the Livonian War. There are remains of the foundations and of the perimeter walls.
The rectangular church was about 47 metres long, and consisted of a single nave of five vaulted bays. Unusually for a Cistercian church it also had a crypt of 10 bays containing two aisles, which was used not only as a place of burial but also as a place of shelter during hostilities. To the south of the church were attached the conventual buildings in the usual form of three ranges arranged in a square round a cloister and a central courtyard, with the chapter house in the east range.
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.