To be privately owned
Gülichsburg Castle

The former moated castle Gülichsburg is located in the Schwerfen district of Zülpich in the Euskirchen district.
History+
Gülichsburg Castle was first documented in 1365 as a Jülich fief owned by Wilhelm von Berg. Historians assume that the castle was originally the ancestral seat of the von Schwerfen family. In 1638, Herr von Kaldenbach sold the castle to Engelbert von Gülich zu Berg, after which it received its current name. As the castle never achieved the status of a knight's seat eligible for the state parliament, it was not expanded. In the 19th century, Gülichsburg Castle changed civilian owners several times and is still used as an agricultural enterprise today.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=568
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: 50.6445, 6.6464