Österreichische Südbahn

• Wiener Neustadt-Baden 16 March 1841
• Baden-Mödling 29 March 1841
• Mödling-Vienna 20 June 1841
• Graz-Celje 2 June 1846
• Celje-Ljubljana 18 June 1849
• Wiener Neustadt-Mürzzuschlag 23 October 1853
• Ljubljana-Postojna 20 November 1856
• Postojna-Trieste 27 July 1857

• 1829: Austrian railway pioneer Franz Xaver Riepl proposed a railway connection from Vienna to the Adriatic Sea, bypassing the Eastern Alps and running via Bruck an der Leitha, Magyaróvár and Szombathely through the west edge of Hungary, and then via Maribor and Ljubljana to Trieste. His plans were adopted by entrepreneur Georgios Sinas. At the same time plans for a direct connection through the Alps were developed and promoted by Archduke John of Austria to open up the Styrian lands beyond Semmering Pass.
• 1839: Departing from the original plans of a connection via Hungary, construction works started on the initial section which ran southwards between Baden, Lower Austria and Wiener Neustadt.
• 1841: Carl Ritter von Ghega started to survey the terrain of the Semmering Pass.
• 5 May 1842: The line from Wien Südbahnhof (Southern Station) was completed to Gloggnitz at the northern foot of the Semmering Pass.
• 21 October 1844: South of the Semmering Pass, the line from Graz northward to Mürzzuschlag (decided on by the Austrian government)) opened; its construction was led by von Ghega.
• 2 June 1846: The southern continuation to Celje was inaugurated.
• 1849: The line was extended to Ljubljana.
• 1848 to 1854: The section over the Semmering Pass was built.
• 17 July 1854: The direct railway connection from Vienna to Ljubljana was inaugurated.
• 1854 to 1857: The final section across the Karst Plateau was built.
• 12 July 1857: The first through train from Vienna to Trieste ran.
• 23 May 1858: The railway was sold to the newly established Austrian Southern Railway Company.
• 1919: In the Treaty of Saint-Germain after World War I, Austria-Hungary was dissolved. Austria lost all of the Southern Railway south of the station at Spielfeld (Špilje), which became the new border station to the Kingdom of Serbs, Croats and Slovenes (Kingdom of Yugoslavia from 1929, present-day Slovenia).
• 1923: The Austrian Federal Railways took over the Austrian section.
• 1966: The tracks from Vienna to Graz and Slovenia were completely electrified.
• 2007: Border controls were abolished with Slovenia's accession to the Schengen Area.