Wikipedia
Mittelbaden (German: "Middle Baden") is an vaguely defined region in the Baden part of Baden-Württemberg. It is customarally used for the region containing the districts of Rastatt, Baden-Baden, and Ortenaukreis. Before the district reform of 1973 it contained the former districts of Baden-Baden, Bühl, Kehl, Rastatt, Offenburg and Wolfach. The region includes the historic counties ( Gaue) of Ufgau and Ortenau.
In a wider sense, Mittelbaden is used to refer to the area between northern Baden ( Mannheim and Rhein-Neckar) and southern Baden ( Emmendingen, Freiburg, Lörrach and Konstanz). In this sense, the term can include the regions of Karlsruhe, Pforzheim and Enzkreis.
Unlike Südbaden and Nordbaden, Mittelbaden has never been an official term for a district or area.