The remains of the Castle can be visited
Koppenstein Castle

Koppenstein Castle Ruin is located on the Koppensteiner Höhe near Henau in the Rhein-Hunsrück district of Rhineland-Palatinate.
History+
The origins of Koppenstein mountain date back to the 12th century, with archaeological finds such as ditches and stone walls suggesting an earlier settlement. The ruins visible today were built after 1325 by the Counts of Sponheim. In 1330, the settlement at the foot of the castle was granted town rights. During the Thirty Years' War, both the castle and the town were abandoned and fell into disrepair. In the early 19th century, the castle ruin served as a hiding place for the loot of the robber Schinderhannes.
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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: 49.8768, 7.4893