For the expansion of the line, a double-track S-Bahn line will be created between " Hasselbrook " and " Ahrensburg ", and a single-track S-Bahn line to " Gartenholz ", then the S-Bahn trains will switch to the long-distance network and cross over this " Bad Oldesloe ". The new line has a length of around 20 km, the total length of the route between " Hasselbrook " and Bad Oldesloe is 35.9 km. The route is planning divided into the four sections `` Hasselbrook - Luetkensallee ", `` Luetkensallee - state border Hamburg / Schleswig-Holstein ", `` state border - garden wood " and `` garden wood - Bad Oldesloe ". The first three are also the sections that have been or will be individually plan approval. No separate approval procedure is required for the fourth section, as no construction work is planned for it.