To be privately owned
Miller-von-Aichholz Castle

The Miller-von-Aichholz-Schlössel, also known as Europahaus Wien, located at Linzerstraße 429, was originally a baroque hunting lodge in Hütteldorf and today belongs to Vienna's 14th district, Penzing.
The castle was built around 1750 by Johann Georg Freiherr von Grechtler, an army supplier to Empress Maria Theresia. After Grechtler's death, the castle came into the possession of the Liechtenstein family and then to Counts Paul and Nikolaus Esterházy, who used the castle as a summer residence.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Miller-von-Aichholz-Schl%C3%B6ssel_01_.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: 48.2037, 16.2532