The network covers about , and serves 68 stations. It consists of two trunk routes crossing the city in an east-west direction – the northern "Hamburg-Altona link line" and the southern "City S-Bahn" – and six connecting routes (two in the western part of the city and four in the eastern part). The trunk routes connect at Altona and Hauptbahnhof. 113.2 km are separated from other rail services, 31.9 km are shared with regional and cargo traffic. About 12.5 km is in tunnel, 7.9 km are single track.