To be privately owned
Hausneindorf Castle

Burg Hausneindorf, a hilltop castle, stands on a plateau above the Selke river in the Harz foothills. Its history is marked by destruction, reconstruction, and a later transformation.
History+
Around the year 1140, Burg Hausneindorf was founded by Henry the Lion as part of the County of Blankenburg. In 1168, it was destroyed, but reconstruction followed in 1172. Later, the complex passed into the possession of the Bishopric of Halberstadt and was first documented in 1310 when it was held as collateral by the County of Regenstein. Between 1429 and 1573, the castle was pledged to the Lords of Hoym. A change occurred in 1711 when it was converted into a Prussian state domain, which altered its original structure through agricultural use.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Roland Neubert, Halle (Saale)
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: 51.8400, 11.2706