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

The Waldsteinburg ruin, also known as the Red Castle, is on the Großer Waldstein in the Fichtelgebirge. This castle complex is also referred to as the Westburg.
History+
The Waldsteinburg, first mentioned around 1350, was built by the Knights of Sparneck to replace an older Eastburg that no longer met the demands of the time. The Sparnecks, a ministerial family, ruled over a vast territory. Rüdiger von Sparneck granted Münchberg the Nuremberg city rights in 1364. The castle played an important role in the power structure of the western Egerland, especially as the center of power of the Holy Roman Empire under Emperor Charles IV moved closer. In the 15th century, Hans I. von Sparneck temporarily pledged the castle, but he and his brothers succeeded in subordinating it as a fief of the emperor. In 1523, the Waldsteinburg was destroyed by the Swabian League.
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: 50.1296, 11.8528