The remains of the Castle can be visited
Krögelstein Castle (Ruin)

In the Krögelstein district of the town of Hollfeld in the Bayreuth district, the Krögelstein Ruin rises on a rocky spur.
History+
The existence of a castle at this location is presumed for the period between 1149 and 1239, when the noble lords of Krögelstein resided here. However, a documentary mention as a “castrum” only occurred in 1328. After the extinction of the Krögelstein family in the 13th century, the castle passed to the Prince-Bishopric of Bamberg. Bishop Wulfing von Stubenberg pledged the complex to the Bamberg Cathedral Chapter in 1313. From 1400, Krögelstein was primarily administered by Bamberg officials.
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: 49.9760, 11.2744