This line was used by mixed trains that carried both iron ore and passengers from Ghelari to Govăjdia and Hunedoara's ironworks.

In 1859 they started digging a 600 m (2,000 ft)-long tunnel from the main mine in Ghelari to Retișoara's valley which was completed in 1866 at a cost of 111,768 Krones and 50 Fillérs.

Meanwhile, they built a 790 metres (2,590 feet)-long, 633 mm gauge railway specially for horse-drawn ore cars.

At the end of the line they built a 160-metre-long chute where they dumped the iron ore to the Retișoara's valley floor which was 90–100 m (300–330 ft) lower than the level of the tunnel's exit.

The altitude difference between the "Lukács László" mining face from the central mine in Ghelari and the throat of the blast furnace in Govăjdia was 260 metres (850 feet); to compensate they built a 5,120-metre-long, 633 mm gauge, divided in three sections by the chutes from Nădrab and Retișoara at a total cost of 20,000 Krones.

However, after the start of the 4th blast furnace the existing ropeway conveyor system proved to be insufficient in ensuring the iron ore needs for all four blast furnaces, so they decided to build a second ropeway conveyor system between Ghelari and Hunedoara parallel to the existing one.

The trackbed preparation work began in 1888 and in 1897 and 1898 were so advanced, that for the line construction the decision steps were made after the connection of the Ghelari mine railway to the Retișoara inclined plane and after the overhaul of the Retișoara inclined plane, further more the legal occupation of the necessary terrain for the railway has started, the surveying of the trackbed was done successfully between January 9–13, 1899, the ministry of commerce asked for a visit from the government that was held at the Hunedoara town hall on 14 February 1899, the construction authorization was given verbally on the mining company's responsibility.

The contract for the construction and usage of the railway was made between three Austrian companies called Gfrerer, Schoch, and Grossmann under the ordinance number 24089 from 15 March 1899 issued by the Hungarian Kingdom's Finance Ministry.

The Transylvanian Mining Railway starts at Hunedoara, passes over the Zlaști valley, and through the 747 m (2,451 ft) tunnel at Cățănaș into Govăjdia valley from where it goes to Retişoara valley that belongs to Ghelari, where it ends at the base of the inclined plane at a total length of 16 km (9.9 mi), with a 760mm gauge built exclusively for steam locomotive usage, the highest incline on the open line was 27‰, in the stations 25‰, the tightest turn radius on the open track was 50 metres, in stations 50 metres.

The distance between tracks in the stations measured from the centre was 3 metres, considering the largest with of the rolling stock of 2.2 meters.

The Transylvanian Mining Railway had four stations, at Hunedoara, Govăjdia, Nădrab, and Retișoara, and four halts: two at Zlaști, one at Cățănaș, and one at Tulea.

The notes gathered by the Hungarian Kingdom's ministry of commerce at the time of visit of the government, were approved under the ordinance number 14230 on 27 April 1899, in the meantime the construction authorization was finally given.

The terminus at Retișoara along with the last three km of railway were closed in the early 1970s, after a different tunnel was constructed in the mid-1960s between the underground mines from Ghelari and the iron ore processing plant from Teliucu Inferior.

One Reşiţa steam locomotive number 12F was transformed into a mobile heating unit for passenger cars in winters.

In 1990 the passenger service ceased, meantime at the loco shed worked around 120 employees in three shifts which were conductors, mechanics, drivers, track maintenance, etc.

On the 13 km long segment they transported dolomite, talc and limestone to the limeworks from Zlaşti and the steelworks in Hunedoara until 2000.

The last three bridges and the last 2.3 km long segment operated until October 2008 for transportation of limestone from the improvised loading station made in the former West-Station of Hunedoara, until the limeworks at Zlaști.

In the summer of 2009 due to economical reasons the management of the limeworks decided to scrap the last 2.3 km segment of railway.

Today the tunnel is in excellent condition, it is open and can be traversed by bicycle, on foot or by motorized all-terrain vehicles serving as a shortcut from to Govăjdia.

The last two L45H class locomotives and the last ten "K" type hopper cars were used until the autumn of 2008 for transportation of limestone from the improvised loading station at Hunedoara West-Station to the limeworks from Zlaşti.

[3] In the summer of 2010 a committee from the culture ministry was sent to inspect what could be saved and classed urgently as a historical monument.

Under this period the local authorities were compelled to produce the necessary documents for this line to receive the permanent historical monument status.

[5] In the summer of 2011 the temporary historic monument status had expired since the local authorities failed to produce the necessary documents.