The remains of the Castle can be visited
Gösting Castle

In the 13th district of Gösting, high above Graz, lies the Gösting Castle Ruin, a hilltop castle that secured the Mur valley passage and offered views over the Graz basin.
History+
The origins of Gösting Castle date back to the 11th century, with its first documented mention in 1042. Emperor Henry III at that time granted land to Margrave Gottfried, who later bequeathed Gösting to his brother Adalbero of Würzburg. The castle changed hands multiple times, including the Eppensteiners and Traungauers, remaining in princely possession until the 17th century. In the 15th century, the complex was expanded into a fortress to provide protection against threats from Turks and Hungarians, and served as part of an early warning system. An event in 1723, when lightning struck the gunpowder magazine, led to the destruction of large parts of the castle. Reconstruction did not occur; instead, the baroque Gösting Castle was built at the foot of the mountain. From 1790, decay set in, and in the 19th century, parts of the walls were dismantled for railway construction.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.at
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Location: 47.1038, 15.3814