The remains of the Castle can be visited
Treis Castle

The castle ruin Treis, also known as Treisburg, is a historical structure in the municipality of Treis-Karden on the Moselle. It is on a mountain spur, surrounded by the Flaumbach and Dünnbach streams.
History+
The exact date of construction of Treis Castle is not recorded, but its erection is presumed to have taken place in the second half of the 11th century. Verified historical reports date the existence of a castle in Treis to the year 1121, when it was destroyed by Henry V. In 1148, the castle was in the possession of the Rhenish Count Palatine Hermann von Stahleck. Due to disputes over the Palatinate office, the castle came under the influence of Trier and was finally conquered by the Archbishop Albero of Trier, thus becoming property of the Archbishopric. During the 12th and 13th centuries, control of the complex apparently lay with the Archdeacon of Karden, before it fell into the possession of Kurtrier in the late 13th century, and thus under the control of the Archbishop of Trier.
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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: 50.1656, 7.2987