The architecture of the Bundesbank's tower building, Cash Department building and guest house at the Bank's Bockenheim campus is in the tradition of classical modernism and can be described as belonging to the Brutalist style. The French architect Le Corbusier coined the term "beton brut", or "raw concrete", meaning the grey unfinished surface of the raw reinforced concrete, which he used as a design feature in his buildings. This conspicuous use of reinforced concrete became an international trend in the 1960s and 1970s and was the preferred architectural style for public buildings around the world, including Germany. This style is characterised by the visibility of the construction and the use of raw, unprocessed building materials, which are not subsequently encased.