The 1878 Berlin Congress permitted Austria-Hungary to occupy and govern former Ottoman Bosnia-Hercegovina. Soon afterwards the Austro-Hungarian military built a 190 km long line from Bosanski Brod to Zenica in order to supply the troops. It was built as a narrow gauge railway, using the 760 mm (2ft 515/16in) track material and rolling stock previously used by the contractor, building the then just finished Temesvar – Osova line. Step by step the Bosanski Brod – Zenica line was extended, finally reaching the capital and largest city of Bosnia-Hercegovina, Sarajevo, in 1882. With a length of 268 km the Bosanski Brod to Sarajevo line formed the nucleus of a narrow gauge Railway network, which, at the outbreak of World War I, had a total length of 1.098 km.
Initially small 0-4-0T locomotives, taken over from the contractor, were used. With the system constantly growing, they were soon found unsuitable and larger and more modern locomotives were introduced. Until 1907 all locomotives used saturatedspeed of 60 kph, which was well above the then standard 35 kph and led to an acceleration of passenger services on the mainline from Bosanski Brod to Sarajevo. The locomotives proved to be an immediate success and remained on the line to Sarajevo until 1947, when the standard gauge line from Šamac to Sarajevo was opened, replacing the narrow gauge line. The locomotives, which had become JŽ class 73 in the state railway’s numbering scheme, were transferred to other lines. By 1965 22 locomotives of JŽ class 73 were still in service, with five of them allocated to the Belgrade division and the remainder to the Sarajevo division. The last engines were only withdrawn in the 1970s with three locomotives being preserved. While JŽ 73-002 resides at the railway museum in Pozega (Western Serbia), JŽ 73-018 was plinthed on a piece of track near a railway bridge over the river Neretva in Bosnia, which was blown up in 1943 by partisans, while a train was crossing it. The remains of the bridge, the locomotive and a van, are leftovers from a 1960s film set, depicting the battle of the Neretva.
