Together they were about ten kilometres long. This was the last U-Bahn construction in Berlin before the First World War, which began on 1 August 1914. No more U-Bahn lines were completed until ten years later. A gift U-Bahn line The southern end of the Wilmersdorf-Dahlemer U-Bahn did not hold good prospects for an extension. The Dahlem line had been unprofitable since it opened and only a single car was operated from Breitenbachplatz to Thielplatz as a so-called "solo car". Greater Berlin, which was united in 1920, demanded that the Prussian government or the Dahlem Commission (Dahlemkommission) take over the line (including the operating cost grants) and took legal action in the Reichsgericht (supreme court) to this end. However, in the years that followed, the financial situation of the line improved considerably with increasing development. The Prussian government was finally able to hand over the line to the city free of charge and debt-free on 1 January 1928. At the same time, the Sommerfeld group, which owned large areas in the southwest of Berlin that were still undeveloped, offered free land and the assumption of construction costs for an extension of the line to Krumme Lanke. In fact, the city was gifted three kilometres of U-Bahn. The line would have the following stations, which are all located in a cutting: Oskar-Helene-Heim Onkel Toms Hütte Krumme Lanke (terminus with a four-track workshop and storage hall in front) This section went into service on 22 December 1929. The Onkel Toms Hütte ("Uncle Tom's Cabin") station and housing estate were named after a nearby restaurant of the same name. The Krumme Lanke station received a New Objectivity style entrance building, which was one of Alfred Grenander's late works. The station forecourt was named after him on 6 June 2009. Since the building had become dilapidated, it had to be demolished in 1988. A good replica was built in 1989. The terminus of today's U3 line is named after a nearby lake. A workshop consisting of a carriage shed with a workshop building was built at Krumme Lanke station. However, due to a lack of capacity, the workshop was closed in 1968 and necessary repairs were outsourced to the Grunewald workshop. In the years that followed, the carriage shed was primarily used as a storage facility, where minor repairs such as changing lamps were only occasionally carried out. Years of not investing in the