To be privately owned
Erpenburg Castle (Brenken)

Erpernburg Castle, a complex, is situated above the Alme Valley in Brenken, North Rhine-Westphalia. It is an example of the development of a noble residence from the valley to the heights, ranging from Baroque to Classicism.
History+
In the 16th century, the Lords of and to Brenken relocated their main residence from the Niederburg in the valley to an elevated position and began constructing Erpernburg Castle. The complex suffered damage during the Thirty Years' War and in a fire in 1684. An expansion of the current castle complex began in the 18th century under Ferdinand von Brenke and his wife Juliane von Westfalen. Between 1712 and 1723, the two-story manor house with a hip roof and four attached tower projections was built, with Nikolaus Wurmstich mentioned as the master mason.
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: 51.5920, 8.5985