The remains of the Castle can be visited
Scharfenstein Castle (Ruin) (Kiedrich)

The Scharfenstein ruin in Kiedrich in the Rheingau-Taunus district offers expansive views over the surrounding vineyards. This once significant state castle of the Archbishopric of Mainz is today a striking medieval architecture.
History+
The origins of Scharfenstein Castle date back to 1160, when it was built as a state castle under Archbishop Christian I von Buch. From 1191, it was inhabited by castellans who subsequently adopted the name "von Scharfenstein". In the 13th century, the castle served as an archiepiscopal residence on several occasions. The castle's tower has adorned the coat of arms of the municipality of Kiedrich since the 14th century. From 1686, the complex progressively deteriorated and became uninhabitable. In 1962, the remaining castle buildings were removed, while the keep underwent renovation in 2008 and 2009.
Source: Wikipedia · Licence: CC BY-SA 4.0
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: 50.0477, 8.0815