The remains of the Castle can be visited
Randeck Castle

On a rocky outcrop on the northern edge of the Altmühl valley, high above the market town of Essing, is the castle ruin Randeck. This hilltop castle in Lower Bavaria.
History+
The origins of the fortification in Randeck likely date back to the 10th century, when Duke Arnulf I of Bavaria had a defensive structure built here against Hungarian incursions. The current castle was constructed in the 11th and 12th centuries by the Lords of Randeck. In 1298, the castle passed to the Abensberger Babonen, who were known as robber knights. After their extinction in 1485, Randeck fell to the Duchy of Bavaria. Numerous changes of ownership followed, including Leonhard von Eck (1529), Otto Heinrich von Schwarzenberg (1565), Alexius Fugger (1594), and Duke Wilhelm of Bavaria (1596). During the Thirty Years' War, the castle was severely damaged by Swedish troops in 1634.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Mobile Geschichte
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: 48.9380, 11.7896