Abbatia Lubensis abbey

Lubiąż Abbey (German: Kloster Leubus; Polish: Opactwo cystersów w Lubiążu), also commonly known in English as Leubus Abbey, is a former Cistercian monastery in Lubiąż, in the Lower Silesian Voivodeship of southwestern Poland, located about 54 km (34 mi) northwest of Wrocław. The abbey, established in 1175, is one of the largest Christian architectural complexes in the world and is considered a masterpiece of Baroque Silesian architecture.

The area of the roofs is about 25,000 square metres. The façade, with a length of 223 m (732 ft), is the longest in Europe after that of El Escorial in Spain. In the crypts are 98 well-preserved mummies of Silesian dukes.

Built over centuries, the abbey - the biggest Cistercian abbey in the world - is currently rated in the highest class ("0") of landmarks of the world's cultural heritage.

The abbey is situated near a ford across the Oder river, where a Benedictine monastery and church of Saint James may have been established about 1150, but had already been abandoned before 1163. At this time the area belonged to the Duchy of Silesia, bequeathed by Duke Bolesław III Wrymouth of Poland to his eldest son Władysław II in 1138. In a fratricidal conflict of the Polish Piast dynasty, Władysław was expelled by his younger brother and fled to Altenburg in the Holy Roman Empire. With the aid by Emperor Frederick Barbarossa, however, his sons were restored to their Silesian heritage in 1163.

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Wikipedia