The cloister’s wing on the Schlossplatz and Franz Joseph-Platz was once Schwarzenberg Palace, which was in the family’s possession starting in 1698. It was built in the late 17th and early 18th centuries and the ground floor contains the remains of walls from the previous building. The streetside exterior has a gable with the Schwarzenberg family crest. In the interior, the staircase and a number of rooms with 18th-century plasterwork are of note, including the double-height ballroom, which currently serves as the chapel.
The building is also the birthplace of Dipl. Ing. Eduard Hartmann (* 3 September 1904 in Laxenburg, + 14 October 1966 in Vienna), who served as Federal Minister of Agriculture and Forestry as well as the provincial governor of Lower Austria. His forebears acquired the property from the Schwarzenberg family in 1868.
In 1912/13 it was purchased by the Sisters of Mercy of the Holy Cross for use as a provincial house; thanks to the purchase of the adjacent ‘Zum goldenen Stern’ inn in 1912, the cloister was able to further expand with annexes such as school buildings, a farmyard and an old-age home.
Parts of the cloister were used as a military hospital during the Second World War. Extensive modernisation work is currently underway for nursing and old-age care.