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Ernst August Stollen Bogen. Ernst August Stollen The Ernst August tunnel part of the Upper Harz Water Regale network in Germany's Harz mountains Foto aufgenommen von Benutzer Benutzer AxelHH Axel Hindemith original upload log page de ErnstAugustStollenBogen AxelHH bytes no Information Ernst August Stollen Benutzer AxelHH