The remains of the Castle can be visited
Twimberg Castle

The castle ruin of Twimberg, a hilltop castle, stands above the village of Twimberg in Carinthia. Strategically located at the mouth of the Waldensteiner Graben into the Lavanttal, it once served as a fortified stronghold.
History+
The origins of the castle and the surrounding area date back to 931, when they were handed over to the Archdiocese of Salzburg. In the early 14th century, specifically between 1326 and 1329, the castle changed hands when the then feudal lord Hadneid von Weissenegg sold it to Bishop Dietrich von Lavant. Under Bishop Dietrich, the complex underwent an expansion with the construction of the keep and a new outer wall.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Bad_St_Leonhard_Twimberg_Burgruine_Twimberg_01102012_977.jpg
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: 46.9165, 14.8465