To be privately owned
Thangelstedt Castle
Thangelstedt Castle, an estate in Thuringia, has a history dating back to the 15th century. Originally built as a manor house, it changed hands multiple times.
History+
The origins of Thangelstedt Castle lie in the 15th century, when it was constructed as a manor house. In 1488, the Count of Gleichen-Blankenhain sold the property to the von Bünau family. Later, in 1681, Christoph Friedrich von Thangel, a princely councilor and master huntsman from Weimar, acquired the knight's estate for 5000 guilders. At the beginning of the 20th century, the castle passed into the possession of Baron von Gross, whose family still owns it today.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: https://commons.wikimedia.org/wiki/File:Schloss_Thangelstedt.JPG
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: 50.8442, 11.2790