The line runs for 7.4 km from the Starnberg wing of Munich Hauptbahnhof to Munich-Pasing station.

The line from the Starnberg Station in Munich via Pasing to Planegg was built in accordance with an agreement of 5 November 1853 between the Royal Bavarian State Railways (German: Königlich Bayerische Staats-Eisenbahnen; K.Bay.Sts.B.)

The line was extended to Gauting on 16 July, to Mühlthal on 16 September and to Starnberg on 28 November 1854.

On 1 January 1862 the line was purchased by the Bavarian government, which had previously leased and operated it.

The line was continued to the south by a private railway company, Lokalbahn AG (LAG), which was granted a concession by the then still independent town of Partenkirchen on 23 September 1888 to build and operate a local railway from Murnau.

At the turn of the 20th century plans to build a railway line between Garmisch-Partenkirchen and Innsbruck were advanced and on 22 November 1904 a treaty was signed by Bavaria and Austria.

's purchase of the LAG's infrastructure on 1 January 1908 for 3.5 million gold marks and the subsequent upgrade of the line.

The Mittenwald Railway from Innsbruck to Garmisch, which was completed in 1912, was from the beginning planned as an electrified line, but electrical operations from Garmisch to the Austrian border were delayed to 25 April 1913 because the power station and deliveries of locomotives were not complete.

It was not until 1924, with the commissioning of the Walchensee Hydroelectric Power Station, that the long-standing electrification plans were completed.

On 3 December 1924, electrical services commenced on the Garmisch-Murnau route and on 5 January 1925 they were extended to Weilheim.

Since the Murnau–Garmisch section was built as a local railway, it needed to be upgraded in a short period of time.

There were more problems on the Hechendorf-Murnau section, including a 2.6% grade, which sometimes required trains had to be so assisted by pusher locomotives.

For these reasons, on 26 and 27 March 1935 the management board of Deutsche Reichsbahn (German Railways) agreed to the duplication of the Huglfing–Hechendorf section.

Wilzhofen, Polling and Farchant were preserved as crossing loops, but in Diemendorf the second track was dismantled in 1996.

Additionally, some Intercity-Express trains run on Saturdays and Sundays, taking about 90 minutes, some continuing to Innsbruck.