The remains of the Castle can be visited
Schaunberg Castle

The Schaunberg castle ruin, once the largest defensive structure in Upper Austria and ancestral seat of the Counts of Schaunberg, stands at an altitude of approximately 399 meters in the village of Schaunberg in the Eferding district.
History+
The castle's origins date back to the mid-12th century, when Heinricus de Scovenberch began its construction. The Schaunbergers, who descended from the Counts of Julbach and held the Danube toll in Aschach as an imperial fief, sought imperial immediacy in the 14th century.
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Location: 48.3412, 13.9776