To be privately owned
Brunnwald Castle

A historic hunting lodge, Brunnwald Castle, stands amidst the Brunnwald forest in Upper Austria. Originally built in the 18th century, it was rebuilt after a fire and now serves as a privately owned estate.
History+
Brunnwald Castle was constructed between 1724 and 1727 as a hunting lodge for the Starhemberg family. A fire in 1898 largely destroyed the structure, but it was rebuilt in 1905, at which time the four-story tower was added. During the Nazi era, the castle was confiscated in 1939 and used as a mothers' home. After World War II, it served as a venue for Protestant church services and housed a maternity ward. Later, it became a Red Cross convalescent home, stood vacant for a period, and was leased to a Spanish association and as a children's home from 1965 to 1982. Since 1993, it has been operated as a guest and residential facility.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Bad_Leonfelden_%28Schloss_Brunnwald-1%29.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: 48.5192, 14.2502