The ünauCross–Grünau Cross–Berlin Brandenburg Airport railway is a railway line in the south of Berlin, the capital of Germany, and in the adjacent areas of Brandenburg. It is used by the Berlin S-Bahn. The first, section was opened in 1962 and served mainly as a connection to Berlin Schönefeld Airport and the associated long-distance station. In 2011, a extension went into operation to connect with Berlin Brandenburg Airport (BER). Due to delays in the commissioning of BER Airport, this section has only been used for public transport since October 2020.
History
The only railway between the radial Berlin–Dresden and Berlin–Görlitz railways until the 1930s was the Neukölln-Mittenwalde Railway, which was also a radial line. The latter also served the village of Schönefeld. Plans for a tangential connection with Berlin's developing railway bypass had been developed for several decades, but they were only actually realised west of the Berlin–Halle railway (Anhalter Bahn). During the Nazi period, the Outer Freight Ring (Güteraußenring, GAR) was built to a temporary low standard; this ran in the area of the southern Berlin city boundary from the Berlin–Halle railway to the east. After the Second World War, passenger traffic ran briefly between Berlin-Grünau and Lichtenrade via Schönefeld and later, between 1955 and 1958, passenger traffic ran again from Grünau to Großziethen.
As a result of the divisions of Germany and Berlin, through rail traffic between most of the surrounding areas and West Berlin (with the exception of the S-Bahn) was cut off in the early 1950s. The traffic ran from the southern radial lines over the beginning of the Berlin outer ring (Berliner Außenring, BAR), which was built in the eastern part of Berlin in the 1950s. Since it was still possible to move largely unhindered between the eastern and western parts of the city, control stations were also set up at the borders between East Berlin and the surrounding area where passengers were checked before they travelled to Berlin. Such a control station was also built in Schönefeld. The station did not serve public transport, but travellers passing through Berlin-Schönefeld Airport, which was opened for civil use in 1955, could use the trains stopping there.
In order to improve access to the airport, an S-Bahn line was planned to the airport as early as 1958. There were also considerations of extending the line to the west to Rangsdorf or along the BAR to Ludwigsfelde. The construction of the Berlin Wall on 13 August 1961 made a railway connection even more urgent. Travellers from the areas to the south of Berlin would be able to change to the S-Bahn in Schönefeld. So soon afterwards work started on the construction of the line.
S-Bahn line to Schönefeld Airport
Work on the line began at the end of September 1961. A second track was built between Altglienicke and Schoenefeld (except under the Waltersdorfer Chaussee underpass) and the infrastructure in the Altglienicke area had to be rebuilt so that an approach road to an expressway could be built next to the railway. The Germanenstraße road bridge was demolished and replaced by a pedestrian bridge with platform access. Grünbergallee station (originally planned with the name of Falkenhöhe) was rebuilt and the former halt of Schönefeld Siedlung on the Outer Freight Ring was closed. The facilities of Schoenefeld station, now serviced by ordinary public transport services, were extended slightly. A new S-Bahn platform and a pedestrian bridge were built and a station building was built in 1962. Nevertheless, the station remained provisional for a long time.
The line went into operation on 26 February 1962, but Grünbergallee station did not open until 27 May 1962. A possible extension of the S-Bahn along the outer ring towards Wuhlheide was prepared at the Grünau Cross (Grünauer Kreuz), where the BAR crosses the Berlin–Görlitz railway. The power supply of the line was built with a provisional substation at Grünau Cross, which was later replaced by a new building.
From 1985 to 1987, the section between Grünau Cross and Altglienicke was upgraded to two tracks. This increased the efficiency of the line. The ultimate goal was to allow a third group of services (i.e., three trains per direction at 20-minute intervals) to better serve the new development areas in the Altglienicke area. However, this increase in services did not occur. The last single-track section under the Waltersdorfer Chaussee bridge was eliminated in 1991.