To be privately owned
Zwickledt Castle

In Wernstein am Inn in Upper Austria, Austria, stands Zwickledt Castle, a former free seat. The estate has an intriguing history of ownership.
History+
The early history of Zwickledt Castle is only sparsely documented, but it is presumed to have originally belonged to the Neuburg dominion. In 1576, Count Julius von Salm und Neuburg am Inn transferred the small castle, along with ten associated houses, to his administrator Leonhard Schmelzing. In the same year, Emperor Maximilian II elevated Leonhard and his brother Bernhard to the nobility. The Schmelzing family was granted the noble predicate “von Wernstein” in 1645. They remained owners of Zwickledt until 1852, after which a series of rapid ownership changes ensued. In 1906, Alfred and Hedwig Kubin acquired the property and lived there until their deaths in 1959 (Alfred) and 1948 (Hedwig), respectively.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Schloss_Zwickledt_-_Westseite.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: 48.5023, 13.4759