Municipal residential complex (1,272 apartments, originally 1,382 apartments), built 1927-1930 according to plans by Karl Ehn (opening on October 12, 1930) on Hagenwiese, named (1930) after the political economist, social economist and founder of Marxism, Karl Marx. The Karl-Marx-Hof was already planned in Red Vienna as a showcase project for municipal housing. The Karl-Marx-Hof subsequently became an icon of Red Vienna, the most famous superblock in the city.[6]. It found and continues to find great interest among tourists from all over the world interested in architecture. Its outstanding position in municipal housing during the interwar period was also recognized in the Second Republic in the form of a stamp from the Austrian Post’s “Building Series”.