The remains of the Castle can be visited
Grünstein Castle (Ruin)
In the Grünstein district of Gefrees, in the Bayreuth district in Upper Franconia, stands the Grünstein Ruin. This castle complex, situated on a low mountain spur, was built in the 14th century.
History+
The origins of Grünstein Castle, which likely dates back to the Walpoten, extend into the 14th century. As early as 1332, it was mentioned as Butzengerute in the Henneberg enfeoffment register. In 1361, the Nuremberg Burgrave Friedrich V permitted the brothers Hans and Arnold von Hirschberg to rebuild the complex, which was already referred to as a castle site at that time, reserving rights of access. This reconstruction was part of the burgraves' expansion policy and served as a counterweight to the aspirations of the Bamberg bishops, whose influence in the region was long disputed and only settled in 1538 by the Treaty of Forchheim. Despite the right of access, the Bamberg bishops exerted influence over Grünstein in the 14th century, and the former Henneberg fief passed to them.
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: 50.0889, 11.7268