To be privately owned
Edelburg Castle

Edelburg, a historic estate in the north of Hemer, is known today as a castle. Together with adjacent buildings, it forms its own district and developed from a moated farm to a water castle.
History+
The first documented mention of Edelburg, then called “Erleborgh,” dates back to 1375. Originally, it was likely a moated farm surrounded by a protective wall. From the 16th century onwards, the owners of Edelburg also acquired the nearby Brelen Castle. Around 1600, building materials from Brelen Castle were used to construct the current main building of Edelburg. During this period, the estate developed into a water castle, a form it retained until the 19th century.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.zeche.org/
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: 51.4103, 7.7907