The remains of the Castle can be visited
Rabenstein Castle

The castle ruin of Rabenstein, a rock castle, is located approximately 300 meters above the market town of St. Paul im Lavanttal. Situated on a rocky hill steeply sloping on three sides, its history ranges from a protective function to destruction and its current state as a freely accessible ruin.
History+
The origins of Rabenstein Castle date back to 1091, when a fortified observation tower stood on this site to secure the then Lavant Castle. With the founding of St. Paul Monastery by Count Engelbert I of Spanheim, the tower was expanded into a protective castle. After Engelbert's death in 1096, the complex passed to his son Siegfried II of Lebenau. The local noble family called themselves Ramenstain, but died out around 1200 with Albertus de Ramenstain. Through the marriage of Ulrich von Peggau-Pfannberg to the last Lebenauer, the castle came into the possession of the Counts of Pfannberg. In 1307, during a conflict over the Bohemian royal crown, the castle was besieged and destroyed by Duke Albrecht I, as the lords of the castle refused to surrender it. Albrecht ceded the property to Bishop Konrad IV von Fohnsdorf, who immediately had the castle rebuilt and expanded. Later, Emperor Frederick III acquired the complex in 1461. After an arson attack in 1636, for which Abbot Marchstaller was suspected as the instigator, the castle fell into ruin and was not rebuilt. In the 19th century, the Rabenstein estate passed into private ownership.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.at/ktn/kaernten.html
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: 46.6888, 14.8721