The remains of the Castle can be visited
Altsummerau Castle (Ruin)

The castle ruin Altsummerau, a former hilltop castle, sits on the Kapf near Rattenweiler, a district of Tettnang.
History+
The construction of Altsummerau Castle is attributed to the Lords of Summerau, its existence already documented in 1152. The complex passed into the possession of the Bishop of Constance. In the 13th century, the castle underwent renovation before being destroyed between 1633 and 1660.
Location+
The ruin of Altsummerau is located south of the Argen on the Kapf near Rattenweiler, a district of Langnau, which belongs to the city of Tettnang in the Bodenseekreis in Baden-Württemberg, Germany. It lies at an elevation of approx. 497 m above sea level.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Altsummerau_5506.jpg
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.
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