Berlin has been one of the most important cities creating modern architecture. As an experienced guide, trained historian and author of several books (including "Architectural History of Berlin") I will take you to exciting architectural gems dating from the 1920s to the 1960s - including projects by Bauhaus founder Walter Gropius, Hans Scharoun and the famous Finnish architect Alvar Aalto. Some of these buildings are World heritage sites recognized by the UNESCO. I will introduce you to the architectural and aesthetic concepts of the architects as well as the social and political background of their works. During the Weimar Republic Berlin became particularly important, as a laboratory for modernism, and later, during the Cold War, West Berlin was seen as the "showcase of the free world", prompting its city planners to foster a modernist program.