To be privately owned
Güsten Castle

Güsten Castle, located in Güsten, a district of Jülich in the Düren district, North Rhine-Westphalia, is, contrary to its name, more a former manor house than a classic castle. Its current appearance as a four-winged complex dates from the second half of the 18th century.
History+
The exact founding history of Güsten Castle is not fully clear. It is presumed that the current complex was built on the foundations of the medieval Harffenburg, which once served as the administrative seat for the bailiffs of Prüm Abbey. However, a confirmed succession from Harffenburg has not been proven. At the beginning of the 19th century, the Tranchot map already showed Güsten Castle as a closed four-winged complex with a moat system. At that time, it was owned by the Coenen family, passed to the Bürsgens family in 1846, and was inherited by a nephew in 1956. Around 1980, Rheinbraun acquired the complex before it was bought by the Hoffarth family in 1996 and converted into an equestrian center. Since April 11, 1990, the building complex has been a listed monument.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=570
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: 50.9570, 6.4321