The Berlin Outer Freight Ring was a planned ring railway around the city of Berlin, Germany. The first sections of a line to the west of the city were built in the early 20th century as part of the Brandenburg Bypass Railway (Umgehungsbahn). Even then, there were plans for a bypass south of Berlin. The first bits were built in the early 1920 and more sections followed in the 1930s. The line could not be completed due to the impact of the Second World War. The completed section consisted of a mainly single-track link running from Teltow to Berlin-Karow to the south and east of Berlin. Part of the route line later became part of the Berlin outer ring.

The Michendorf–Großbeeren railway is an electrified main line railway in the German state of Brandenburg south of Berlin. It went into operation in 1926 and was originally a section of the Brandenburg Bypass Railway, which was built to remove freight traffic from the railways through Berlin. The section between Saarmund and Genshagener Heide has been included in the Berlin Outer Ring since the 1950s.