The remains of the Castle can be visited
Waldschlössel Castle

On the Treutelsberg near Klingenmünster in Rhineland-Palatinate, the Waldschlössel castle ruin is located, one of the oldest castle complexes in the Palatinate. This site, a UNESCO World Heritage site since 2000, is an example of a motte-and-bailey castle primarily revealed through archaeological findings.
History+
The origins of the Waldschlössel date back to between 880 and 920, when a large ring wall was built as an outer bailey. This structure likely served as a refuge castle to protect against Norman invasions. Around 1030, the motte-and-bailey castle was constructed during the Salian period, with remnants of a mortar mixing area, two buildings, fireplaces, and an ore furnace dating from this era. After its destruction in the second third of the 11th century, the castle was rebuilt with structural modifications in the last third of the 11th century. A third period of use followed at the beginning of the 12th century, also after a destruction. Salian King Conrad II is considered a possible builder. Through the territorial policy of Archbishop Adalbert I of Mainz, the castle later came into the possession of the Counts of Saarbrücken and subsequently the Staufer dynasty.
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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: 49.1505, 8.0068