town at its own expenses. A panorama of the fortified abbey can be seen in Matthäus Merian's engraving showing Constance and Petershausen during the siege of 1633. A slow recovery of the abbey began after the end of this destructive war. Petershausen was finally secularised to Baden in 1802; the library was purchased by the University Library Heidelberg. Margrave Charles Frederick of Baden had parts of the abbey rebuilt as a private residence for his sons. The St Gregory Church was demolished in 1832. The remaining premises were later used as a psychiatric hospital and as barracks. They now accommodate a number of administrative and educational functions and the Archaeological Museum of Baden-Württemberg. References Benedictine monasteries in Germany Monasteries in Baden-Württemberg Imperial abbeys disestablished in 1802–03 983 establishments Christian monasteries established in the 10th century 10th-century establishments in Germany