Reichenau Castle in Reichenau an der Rax was first mentioned in records in 1256, when noblemen of the Lords of Pitten-Klamm acquired the property rights.
These property rights were sold in 1311 to the brothers Fallbach on.
Duke Otto the Merry bought the reign of Reichenau and the castle in 1333 and donated the castle to Neuberg Abbey.
The Cistercian monks were resident in Reichenau for over 450 years. Because of the favorable climate, several Neuberg abbots often spent a long time in Reichenau Castle.
In 1784 the reign Reichenau became the property of the Innerberger main union, who used the castle as a residence and home for senior officials.
The last owner, Margarethe Bader-Waissnix, established a foundation in 1992 for the benefit of the municipality of Reichenau. The purpose of the foundation is the establishment of a cultural center. In accordance with this foundation, in 2003 Schloss Reichenau was the main exhibition site of the Lower Austrian Provincial Exhibition. Also in the year 2004 an exhibition could be shown with a big railway exhibition for the anniversary "150 years Semmeringbahn" under the motto "fascination Semmeringbahn".