In 1963, Hans Scharoun and Sergius Ruegenberg were invited to submit designs in a competition for the construction of a new Staatsbibliothek. The guidelines included the development of an overall concept for the Kulturforum and a new course for Potsdamer Straße. Ruegenberg’s design was the only one that foresaw a pedes-trian tunnel under the road with its heavy traffic. The winning design by Scharoun and Hermann Mattern included plans to place Potsdamer Straße where it is today. They saw the street as a “valley,” to which the terrace-like, staggered design of the surrounding buildings Staatsbi-bliothek and Guest House (not built) should refer.