The remains of the Castle can be visited
Balduinstein Castle

The Balduinstein Castle Ruin, a former rock castle in the Rhein-Lahn district of Rhineland-Palatinate, is situated on a rocky spur above the village of Balduinstein and the Lahn River.
History+
The origins of Balduinstein Castle date back to 1319, when Archbishop Balduin of Trier initiated the construction of this fortress. It served as a counterpoint to the neighboring lords of Westerburg, with whom Balduin was feuding. As early as 1321, the settlement of Balduinstein was granted town rights by Emperor Louis the Bavarian. Balduin elevated the settlement to an office and handed over both the castle and the office in 1335 to Knight Dietrich von Staffel, to whom he also pledged the castle in 1339. The von Staffel family remained in possession of the castle until their male line died out in 1683.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=932
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: 50.3442, 7.9736