The Southern Railway () is a railway in Austria that runs from Vienna to Graz and the border with Slovenia at Spielfeld via Semmering and Bruck an der Mur. It is a part of the Austrian Southern Railway that connected Vienna with Trieste, the main seaport of the Austro-Hungarian Monarchy, via Ljubljana. A main obstacle in its construction was getting over the Semmering Pass over the Northern Limestone Alps. The twin-track, electrified section that runs through the current territory of Austria is owned and operated by Austrian Federal Railways (ÖBB) and is one of the major lines in the country.