To be privately owned
Vasoldsberg Castle

Vasoldsberg Castle, originally conceived as a defensive complex, stands on a wooded hill in Styria, Austria.
History+
The origins of Vasoldsberg Castle date back to the early 13th century, though its precise early history remains obscure. The first documented owner, Ulrich von Vasoldsperge, was mentioned in 1252. The castle changed hands multiple times, including the Fuller family and the Bishops of Seckau, before passing to the Styrian sovereign. In 1467, during the unrest surrounding Andreas Baumkircher, Vasoldsberg was occupied by rebellious troops. Emperor Frederick III forced the Bishop of Seckau to relinquish his feudal rights, bringing the castle into Habsburg possession. In the mid-16th century, a comprehensive renovation took place under administrator Kolomann Prunner. Following an arson attack on the manor farm in 1578 and high tax debts that led to its pledging in 1592, further changes of ownership occurred from the 17th century onwards. In the 19th century, it became bourgeois property, and major renovations took place between 1911 and 1914. From 1942 to 1987, it belonged to Steyr-Daimler-Puch AG before becoming private property.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.at
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: 47.0191, 15.5754