The Castle can be visited
Sommerau Castle

The castle stands on the grounds of one of the oldest farms in the municipality, the Pruggenbauer or Stockreiterhof, known since 1331. In 1881, the property came into the possession of the Landauer family, who had the farm buildings demolished in 1884 and the country house Sommerau built in their place. In 1894, the villa passed into the possession of the Hungarian magnate Geza Count Brunsvik de Koromba, who finally expanded it into a castle for 50,000 guilders according to plans by the Graz architect Jellinek. In 1902, the property was sold to the company Holzmann et Companie and converted into a luxury hotel.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Schloss_Sommerau_Spital.jpg
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Location: 47.6042, 15.7342