To be privately owned
Zillbach Castle

Near the village of Zillbach, Zillbach Castle stands. Originally conceived as a hunting lodge, it is linked with the Dukes of Saxe-Eisenach and records visits by Johann Wolfgang von Goethe.
History+
The castle's origins date back to 1543, when Georg Ernst von Henneberg-Schleusingen had the first hunting lodge built in the forests of Zillbach. This structure, which existed until 1759, was described as a defensive-looking, round tower-like building, surrounded by a wall and ancillary buildings. After the extinction of the Henneberg counts in 1583, the lands fell to the Duchy of Saxe-Coburg-Eisenach. Later, dukes such as Johann Ernst and Johann Georg I of Saxe-Eisenach used the area for hunting.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Metilsteiner (talk) / CC BY-SA 3.0 via Wikimedia Commons
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: 50.7037, 10.2942