The remains of the Castle can be visited
Raffenburg Castle

The Raffenburg castle ruin, also known as Raffenberg Castle, is a hilltop castle ruin in Hagen-Hohenlimburg, North Rhine-Westphalia. It sits atop the wooded Raffenberg, surrounded by a nature reserve.
History+
The Raffenburg was most likely founded in the first half of the 13th century, possibly after the murder of Archbishop Engelbert of Berg in 1225 or concurrently with the construction of the Hohenlimburg directly opposite. It served as a border fortification for Electoral Cologne against the County of Limburg. In May 1288, Count Eberhard II of the Marck besieged the castle.
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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: 51.3522, 7.5575