To be privately owned
Schönbühel Castle

In the Lower Austrian municipality of Schönbühel-Aggsbach, Schloss Schönbühel, a complex on the right bank of the Danube, is on an approximately 40-meter-high rock. Originally conceived as a fortress, its origins date back to the early 12th century.
History+
The origins of the castle date back to the early 12th century, when Marchwardus de Schoenbuchele had the complex built as an easily defensible fortress. It is presumed that a Roman fortification already existed at this strategically important location. In 1064, the castle received its own church, which was used for services until 1667. A school was also once housed here. After the extinction of the von Schonpihel family in the early 14th century, the castle changed hands several times, including Conrad von Eisenbeutel and Melk Abbey.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Uwe Klimpke
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 48.2579, 15.3737