Altenburg Abbey () is a Benedictine monastery in Altenburg, Lower Austria. It is situated about to the north of Krems an der Donau in the Waldviertel. It was founded in 1144，by Countess Hildeburg of Poigen-Rebgau. Throughout its history it suffered numerous invasions and attacks, and was destroyed by the Swedes in 1645. Under Emperor Joseph II in 1793 the abbey was forbidden to accept new novices, but unlike many others in Austria it succeeded in remaining functional. The abbey attained its present Baroque form under the direction of abbots Maurus Boxler and Placidus Much. The modernization of the abbey was supervised by the architect Josef Munggenast with support from some of the most distinguished artists and craftsmen of Austria: Paul Troger on the frescoes, Franz Josef Holzinger on the stucco work, and Johann Georg Hoppl on the marbling. The Baroque structure which replaced the earlier Romanesque abbey is said to be one of the finest in Austria. History Altenburg Abbey was founded in 1144 by Countess Hildeburg of Poigen-Rebgau. Archeological excavations carried out by the Federal Monuments Office between 1983 and 2005 have revealed evidence of its dating in the remains of a wall from the 12th century and of a Romanesque cloister dated to the 13th century. The monastery was destroyed and reconstructed as a result of numerous attacks. The first was in 1251 by Hermann V von Baden, followed by several by the Cumans between 1304 and 1327 and during the Hussite Wars from 1427 to 1430. It was attacked by Bohemia, Moravia and Hungary in 1448, and by the Turks in 1552. In 1327, some restoration work was carried out by Gertrude, the widow of Heidenreich von Gars. In 1645, the Swedes destroyed the abbey. Refurbishment took shape after the Thirty Years' War in the 17th and 18th centuries. The abbey took its present form in the Baroque style under the abbots Maurus Boxler and Placidus Much. Work was carried out under the supervision of the architect Josef Munggenast who was assisted by some of Austria's most distinguished artists and craftsmen: Paul Troger for the frescoes, Franz Josef Holzinger for the stucco work, and Johann Georg Hoppl for the marbling. Under Emperor Joseph II in 1793 the abbey was forbidden to accept new novices, but unlike many others in Austria it succeeded in remaining functional. Subsequent to the Revolution of 1848, its debts were cleared by the