To be privately owned
Berg Castle

On the northeastern edge of the Eifel, Burg Berg rises, a former moated castle from the 12th century. Located in Mechernich-Berg in the district of Euskirchen, it presents itself today as a castle house with a freestanding tower, complemented by a former outer bailey situated to the northeast.
History+
The first mention of the settlement of Berg, to which the castle belongs, dates back to the year 699. At that time, Irmina von Oeren, a relative of the Carolingian house, transferred the “villa” Berg to Saint Willibrord.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=568
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: 50.6362, 6.5945