and 30. The 29th and top usable floor, housed a restaurant. Since the renovations, the building now contains 410 offices, 40 conference rooms, and a library. The frame of the building is made entirely of steel. This is highly unusual in central European construction where most buildings use concrete frames. Therefore, even though it is only the 43rd tallest building in Germany, it is actually the tallest building in Germany with a steel frame. The building is protected as a landmark by the North Rhine-Westphalian government. The building received this status very early, less than 30 years after its construction. Preservationists justified their decision, stating that the building, with its eschewal of hierarchical elements in the facade design, was a "vivid example for the understanding of democratic construction in the young West Germany." See also List of tallest buildings in Germany UN Campus, Bonn Buildings and structures completed in 1969 Buildings and structures in Bonn Skyscraper office buildings in Germany