To be privately owned
Wildenhag Castle

Wildenhag Castle, a historic edifice in the Attergau region of Upper Austria, is now privately owned.
History+
The first documented mention of Wildenhag dates back to 1379, when it was owned by the Utzinger family and granted as a fief by Duke Albrecht IV. The Utzingers, a minor noble family from Jetzing, held the estate for generations. In 1449, Emperor Frederick III granted market rights to the Wildenhag property. After the Utzinger line died out in 1554, Wildenhag passed through various hands, including Erasmus von Gera and the Arnsteiner family. From 1583, the estate was merged with Walchen, with the administrative seat moved there, leading to Wildenhag's decay.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Wildenhag-1.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: 47.9074, 13.4907