The Castle can be visited
Ottenstein Castle

Ottenstein Castle, a complex in Austria's Waldviertel region, sits on a hill overlooking the reservoir of the same name. Its history and visible Baroque alterations.
History+
The first documented mention of a Hugo de Ottenstaine dates back to 1177, though the castle's origins likely predate this. Until the first half of the 15th century, Ottenstein was owned by the Ottensteiner family, who were related to the Lords of Rauheneck. After a siege in 1448, Tobias von Rohr, the subsequent owner, was captured due to his transgressions. In 1516, Paul Stodoligk acquired the castle, and under his son Eustach, expansions, including the outer bailey, were realized. In 1536, Ottenstein passed to the Lamberg family, who owned the estate for over 400 years. The Lambergs, elevated to the rank of barons in 1544 and counts in 1667, significantly shaped the castle. During the Thirty Years' War, the castle withstood two sieges in 1622 and 1640. From 1679 onwards, Baroque redesigns were carried out, which characterize its current appearance. The chapel, dedicated to Saint Florian, was stuccoed by Lorando Aliprandi.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.panoramio.com/photo/108469375
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Location: 48.5964, 15.3356