The remains of the Castle can be visited
Klausegg Castle

In the Seetal valley in Lungau stands the castle ruin of Klausegg, a former border fortification. Situated at an altitude of approximately 1287 meters above sea level, it once offered protection against incursions from Styria.
History+
The origins of Klausegg Castle likely date back to the 13th century, when the Archbishops of Salzburg had it built as part of a systematic border defense system against Styria. Together with a barrier wall crossing the valley and a gate, the castle formed a line of defense. In the late 15th century, during the Hungarian Wars, the complex was the scene of military conflicts.
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Location: 47.1552, 13.9622