To be privately owned
Ippenburg Castle

In Lockhausen, a district of Bad Essen in the Osnabrück district, stands Ippenburg Castle, a Neo-Gothic structure. It has been associated with the von dem Bussche-Ippenburg family for over six centuries.
History+
The origins of Ippenburg Castle date back to the late 14th century, when Knight Johann von dem Bussche had a fortified castle built with loopholes and a moat. This fortress, accessible only via a drawbridge and featuring a fortified rampart between two moats, served as a residence until 1811 before being demolished due to dilapidation.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=651
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: 52.3403, 8.3614