To be privately owned
Heltorf Castle

Heltorf Castle, a moated castle in the Düsseldorf district of Angermund, is set within an English landscape garden. It originally served to manage the surrounding agricultural and forestry estates and remains a historical property to this day.
History+
Heltorf is first mentioned in the 11th century as Hof Helethorpe in the rent register of Kaiserswerth Abbey. The early owners were the Lords of Heldorp, with Otto von Heldorp already named as owner in 1167. In 1360, ownership transferred to Thomas von Lohausen, also known as Troisdorf, and his wife Aleide von Geynhoven.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=572
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: 51.3423, 6.7705