To be privately owned
Philippsburg Castle

In the Loga district of the East Frisian town of Leer in Lower Saxony is Philippsburg Castle. Designed purely as a residential building, it features a Dutch Baroque architectural style.
History+
The construction of Philippsburg Castle began in 1730 under Baron Philipp von Wedel. Originally, the building complex featured a two-story central section with a curved gable, while the side wings were single-story. A significant alteration occurred in 1906 when Botho Graf von Wedel added another floor, integrating the original gable into the new structure. The von Wedel family also owned the nearby Evenburg Castle.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: https://de.wikipedia.org/wiki/Datei:Phillipsburg_Leer_Loga.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: 53.2376, 7.4968