To be privately owned
Rennenberg Castle

A stately residence in Linz am Rhein, Rennenberg Castle is a structure built in 1846 and protected as a cultural monument. It once served as a summer retreat and is distinguished by its neoclassical architecture and park grounds.
History+
The construction of Rennenberg Castle was commissioned in 1846 by Friedrich IV of Salm-Kyrburg. It was intended as a summer residence for the Princes of Salm-Kyrburg, whose noble line, however, ended in 1905. The estate also included a hunting lodge, which is now also a protected monument. During World War II, on the night of August 25, 1940, the castle was hit by an incendiary bomb during an air raid, but the resulting fire was extinguished. After a change of ownership in 1992, the property underwent renovation. Two years later, in 1994, the castle and its associated park were designated as a monument zone.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=990
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: 50.5842, 7.2998