To be privately owned
Honrath Castle

Honrath Castle, a castle house, is located in Lohmar-Honrath in the Rhein-Sieg district, North Rhine-Westphalia. It is situated on a ridge that slopes towards the Agger Valley, forming the oldest ensemble of the village together with the adjacent Protestant church.
History+
The first documented mention of the knight's seat Honrath dates to 1117, when God(e)fried transferred his allod “Hagenroth” to Siegburg Abbey. Ownership changed hands several times: It first passed to Theoderich von Hengebach and later to Arnold von Hückeswagen. In 1209, the latter donated the patronage of St. Margaretha Church to the Benedictine convent of Gräfrath, but retained the castle for himself. In 1259, the heirs of Hückeswagen sold the castle and the parish to the Counts of Sayn.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.zeche.org/
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Location: 50.9069, 7.2547