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from München-Heimeranplatz station to a point to the north of Grosshesselohe Isartal station, its track runs parallel with the Munich–Holzkirchen railway, opened from Munich to Grosshesselohe on 24 June 1854 as part of the Bavarian Maximilian's Railway.
from a point to the north of Grosshesselohe Isartal station to Höllriegelskreuth on the Isar Valley Railway, opened by the Lokalbahn AG company (LAG) on 27 July 1891 and electrified from Wolfratshausen to Höllriegelskreuth in May 1960 at 580 volts DC and converted to 15 kV AC on 27 September 1957
S-Bahn services commenced on 28 May 1972 as S-Bahn line 12. It ran to Deisenhofen rather than Höllriegelskreuth until 14 December 2013.
References
Eisenbahnatlas Deutschland (German railway atlas) (2009/2010 ed.). Schweers + Wall. 2009. pp. 107, 164–7. ISBN978-3-89494-139-0.
Wolfgang Klee (1994). Bayerische Eisenbahngeschichte - part 1: 1835-1875, Bayern Report 1 (in German). Fürstenfeldbruck: Hermann Merker Verlag.
Foit, Wolfgang, ed. (2007). Als die Eisenbahn in unsere Heimat kam. Die Geschichte der Maximiliansbahn München–Holzkirchen–Rosenheim (When the railway came into our home. The story of Maximilian's Railway, Munich-Holzkirchen-Rosenheim) (in German). Holzkirchen.{{cite book}}: CS1 maint: location missing publisher (link)