To be privately owned
Grittern Castle (Doverheide)

Grittern Castle, also known as Doverheide, is a castle complex in Doverheide, a district of Hückelhoven in the Heinsberg district, North Rhine-Westphalia. Originally a late medieval moated castle, it is now a listed former manor house whose main building dates back to the 16th century and is part of a series of manor houses in the Rur Valley.
History+
The origins of the late medieval moated castle of Grittern are not fully documented, but it is believed to have been the ancestral seat of the Grittern noble family. In 1535, the property came into the possession of the Lieck family through the marriage of Sophia von Grittern to Dietrich von Lieck. Their descendants, Johann von Lieck and Elise von Wevorde, had the castle house, which is still partially preserved today, built in the late 16th century. In 1654, the castle changed hands again when Elise Christine von Lieck married Wilhelm Degenhard von Hompesch-Bollheim. The Hompesch-Bollheim noble family held the estate until 1840.
Source: Wikipedia · Licence: CC BY-SA 4.0
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: 51.0393, 6.2315