To be privately owned
Burgsteinfurt Castle

Burgsteinfurt Castle, a moated castle, is situated on the edge of the old town of Steinfurt in North Rhine-Westphalia. As the oldest preserved moated castle complex in Westphalia, it sits on an almost circular island, surrounded by the Steinfurter Aa, and today consists of three complexes: the upper castle, the lower castle, and the castle mill.
History+
The origins of the castle date back to 1129, when Rudolf II von Stenvorde, noble lord of Steinfurt, had his main court built. This initially consisted of a square residential tower on an artificially raised hill, surrounded by a moat created by damming the Aa. Shortly thereafter, the Lords of Steinfurt added the Buddenturm on another artificial island to the complex. In 1164, the castle was destroyed in a feud with the Lords of Ascheberg but was rebuilt with the support of Archbishop Rainald von Dassel of Cologne. By the end of the 12th century, a castle chapel was integrated into the curtain wall. In the mid-13th century, the residential tower was converted into a knight's hall, recognizable by its early Gothic pointed arch windows. At the same time, the two islands were united into a single one and surrounded by a common defensive wall. The outer bailey, which included farm buildings and burgmann residences, also originated in the 13th century.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.zeche.org/
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: 52.1457, 7.3417