Schloss Hollenburg
 Schloss Hollenburg (Slovene: Humberk) is a medieval castle near Köttmannsdorf in Carinthia Austria. It is located on a rock of the northern slope of the Drava valley.One Swiker Lord of Hollenburg in the Duchy of Carinthia was first documented as a witness in the 1142 deed of the foundation of Viktring Abbey.