The line crosses the Berlin city limits and again meets the Berlin outer ring. Berlin Schönefeld Airport station has an island platform for the S-Bahn with two S-Bahn tracks; it formerly had three island platforms for mainline services. Originally, no extension of the S-Bahn line was planned. Therefore, the extension of the S-Bahn line continues on the axis of the former long-distance tracks from the southern island platform, which was therefore taken out of service. The outer ring had been four-tracked in this area in the 1980s. The new S-Bahn line uses the two southern tracks of the outer ring. It follows the ring for several kilometres and turns to the south in Waßmannsdorf and runs into Waßmannsdorf station, which is built on an embankment. At Selchow the line meets the long-distance tracks of the Glasower Damm Ost–Bohnsdorf Süd railway and they run together initially in a trough, then through a several kilometre-long tunnel to the east and then northeast to Berlin Brandenburg Airport. This is where the S-Bahn line ends, while the long-distance train tracks continue to the Görlitz Railway. The airport station is only about in a direct line from Schönefeld station, while the S-Bahn line between the two stations is long.
