U4

Transit line

The U4 is a line of the Berlin U-Bahn in Germany, the shortest in Berlin's U-Bahn system with a length of 2.86 kilometres (1.78 mi). It serves five stations, with only the two termini being step-free. Opened in 1910, it is the only subway line in Berlin to have never been extended and the only one to have no night service on weekends. In 1903, Schöneberg a then independent city south-west of the then municipal boundaries of Berlin, planned to develop an underground railway line to improve public transportation. As the line promised less profit for a private investor (up to that point all Berlin U-Bahn lines had been built with private capital), the negotiations with the Berliner Hochbahngesellschaft (Berlin Elevated Railway Company, then the operator of Berlin U-Bahn) were unsuccessful. Consequently, Schöneberg started to build the line itself on 8 December 1908. Two years later, the construction was finished and, on 1 December 1910, the line was put into operation. Although Schöneberg owned the track, upon opening, it handed operations over to the Hochbahngesellschaft. From Wikipedia