The remains of the Castle can be visited
Arnsberg Castle

The Arnsberg Castle Ruin is in Arnsberg, North Rhine-Westphalia, on the Schlossberg. Originally built as a medieval castle by the Counts of Werl-Arnsberg, it evolved into a residential palace and is now a ruin.
History+
The origins of the complex date back to the early 12th century, when the Counts of Werl-Arnsberg established a castle here. Until 1368, it served as the main residence of the counts. After the county passed to the Archbishops and Electors of Cologne, the castle became the administrative center of the Duchy of Westphalia. Elector Salentin von Isenburg had the complex rebuilt in the Renaissance style around 1575.
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Location: 51.4012, 8.0622