raise funds for the association. The building housed the teachers' library which survived two world wars, and today is integrated into the library for educational historical research. The rear of the property contained the association's administrative building, a hotel for members and an exhibition hall. Notable events that took place in the hall include the funeral services for and on 2 February 1919 and, on 4 December 1920, the (Unification Party Congress) of the Communist Party and the USPD. The First Ordinary Congress of the Communist Workers Party of Germany was held in the nearby restaurant, 1–4 August 1920. 's position as a main transport and traffic hub continued to fuel its development. In addition to the three underground lines, long-distance trains and trains ran along the 's viaduct arches. Omnibuses, horse-drawn from 1877 and, after 1898, also electric-powered trams, ran out of in all directions in a star shape. The subway station was designed by Alfred Grenander and followed the colour-coded order of subway stations, which began with green at and ran through to dark red. In the Golden Twenties, was the epitome of the lively, pulsating cosmopolitan city of Berlin, rivalled in the city only by . Many of the buildings and rail bridges surrounding the platz bore large billboards that illuminated the night. The Berlin cigarette company Manoli had a famous billboard at the time which contained a ring of neon tubes that constantly circled a black ball. The proverbial "" of those years was characterized as "". Writer wrote a poem referencing the advert, and the composer Rudolf Nelson made the legendary with the dancer Lucie Berber. The writer named his novel, , after the square, and filmed his 1927 film parts of (Berlin: The Symphony of the Big City) at . Destruction of (1940–1945) One of Berlin's largest air-raid shelters during the Second World War was situated under . It was built between 1941 and 1943 for the by . The war reached in early April 1945. The Berolina statue had already been removed in 1944 and probably melted down for use in arms production. During the Battle of Berlin, Red Army artillery bombarded the area around . The battles of the last days of the war destroyed considerable parts of the historic , as well as many of the buildings around . The had entrenched itself within the tunnels of the underground system. Hours