To be privately owned
Freudensee Castle

On the shore of the Freudensee lake in the Bavarian Forest lies Freudensee Castle, once a seat of power. Now privately owned.
History+
The early years of Freudensee Castle are obscure, but it is believed to have originally belonged to ministerials or noble families. In the 15th century, it came into the direct possession of the Prince-Bishopric of Passau and was restored. Bishop Georg I von Hohenlohe (1390–1423) used it as a hunting lodge. From the 16th century onwards, the castle lost its importance and was abandoned, and the associated administrative court was dissolved. However, the fishing rights remained with the Prince-Bishop.
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: 48.6621, 13.6316