To be privately owned
Fürstenberg Castle

In North Rhine-Westphalia, Fürstenberg Castle stands on an elevated position near Bad Wünnenberg. It is an example of 18th-century architecture.
History+
The origins of the current castle lie in the medieval Vorstenburg, built around 1321/25 by Bishop Bernhard V of Paderborn. Its main purpose was to defend against the noble lords of Büren. Shortly after its construction, the castle was mortgaged, changed hands multiple times, and was eventually destroyed. From 1446, the area came into the possession of the von Westphalen family, who built a new complex on the same site. The northeast tower and vaulted cellars from this period are still preserved today. In the 1780s, Friedrich Wilhelm von Westphalen, Bishop of Hildesheim and Paderborn, had a castle built on the foundations of the demolished fortress to serve as a summer residence.
Source: Wikipedia · Licence: CC BY-SA 4.0
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: 51.5156, 8.7368