To be privately owned
Bipp Castle (Oberbipp)

In the municipality of Oberbipp in the canton of Bern stands Bipp Castle, a 13th-century complex, now privately owned.
History+
The first documented mention of Bipp Castle dates back to 1268. Towards the end of the 13th century, it came into the possession of the Counts of Neuchâtel-Nidau, before passing to the Kyburg family in the mid-14th century. In 1407, the Kyburgs sold the castle to the cities of Bern and Solothurn, who subsequently administered the dominion jointly. Bern acquired the property entirely in 1463 and established the castle as the seat of the Bernese bailiff.
Source: Wikipedia · Licence: CC BY-SA 4.0
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: 47.2636, 7.6519