History:
| 21 Nov. 1896 | Start of building the railway from St. Poelten main station to Kirchberg/Pielach. The engineer was Ing. Josef Fogowiz. Gauge 760mm (narrow gauge). |
| 7 June 1898 | First Train in Kirchberg. Operatet by NÖLB (Niederösterreichische Landesbahnen, Lower Austria Local Railways). |
| 2 July 1898 |
Opening of the part from St. Pölten main station to Kirchberg/Pielach (31.3 km)/td> |
The trains were pulled by the proven Class U (“U” stands for Unzmark/Murtal Railway) built by Locomotive-factory Krauss/Linz.(Journey speed 25km/h). |
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| off 1903 | Because of the good utilization at smaller trains, steam railcars built by company Komerek were used. (Increase of journey speed up to 30 km/h) |
| 1904 | Start of construction from Kirchberg to Laubenbachmühle |
| 5 Aug. 1905 | Opening of this part (length almost 50 km). |
| March 1905 | Start of building the part from Laubenbachmühle to Gusswerk (Stmk.), also known als “Bergstrecke”. |
| 17 Dec. 1906 |
The first freight train should arrive in Mariazell. Because of heavy snow-stroms it only arrived Winterbach. |
| 19 Dec 1906 | The frist freight train finally arrived in Mariazell. |
| 15 July 1907 | The whole railway to Gusswerk was officially openend. |
| 1906 | Newer,stronger superheated steam locomoitves class Mh (“M” for Mariazell, “h” for superheated steam) were commissioned. The locomotive Mh.6 is restored and for nostalgic trains in service. |
| 7 Oct. 1911 | Start of the electric operation on the Mariazell Railway. |
| For that, 16 electric-locos (class 1099, E) were ordered by Krauss & Comp./Linz. They are one of the first single-phase alternating current locomotives. They are the eldest locomotives beeing in service nowadays. The power was supplied by a hydroelectric power station in Wienerbruck (Stierwaschboden), a diesel power station in St. Pölten (closed nowadays). Two substations in Ober-Grafendorf and Kirchberg feeded the voltage into the overhead line. (single-phase alternating currend 6.5 kV, 25 Hz)  |
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| 1923 | A second power station was built in Erlaufboden. In the 1960s both substations were replaced with each in Gösing in Rabenstein. The power stations could yield more electricity than necessary, so they feed the local electrical grid. |
| 15 July 1922 | The Austrian Federal Railways (at that time BBÖ) took over the operation. |
| End of the 1950s |
Rebuilding of class 1099 into their current appearance. |
| 29 Sept. 1988 |
End of operation on the track from Mariazell to Gusswerk (lenght of Mariazell Railway since then 84,5 km) and end of the freight service from Loich to Mariazell. |
| 1995 | New EMUs class 4090/7090/6090 were commissioned. |
| 31 Dec. 1988 | End of freight service on the Mariazell Railway |
| Mai 1995 | Disel railcars class 5090 (no toiletes!) were in operation on the section St. Pölten – Laubenbachmühle. |
| After closing of the Waldviertel Railway and the “Krumpe” from Ruprechtshofen, also disel locomotives class 2095 are on service on the Mariazell Railway up to Mariazell. | |
| 7 Oct 2001 | 90th anniversary of electrict operation. |
| Application of entry into the Guinnesbook of Records for the eldest electric locomotive still beeing in service. | |
| 12 Dec 2010 | The NÖVOG (Niederösterreichse Verkehrsorganisationsgesellschaft, Lower Austria Transport-Organisation Company) took over several railways in Lower Austria. Under that, also the Mariazell Railway. |
| 3 Dec 2011 | The cut of the spade for the new operations center in Laubenbachmühle took place. |
| 27 Oct 2013 | New low-floor EMUs called “Himmelstreppe, Stairway to Heaven” took over the traffic on the Mariazell Railway. The old class 1099 is still in operation with the nostalgic train “Ötschbär”.
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| June 2014 | The new frequency converter station in Klangen started to work. It replaced the two old hydroelectric power stations in Erlaufboden and Stierwaschboden. |
| Summer 2015 | The Mariazell Railway is part of the regional exhibition “ötscher:reich”. |
| 3 May 2017 | The cut of the spade for the new operations center in St. Pölten took place. In the future, there will be the service for the nostalgic vehicles. Also the head office will be there. |
| 3 July 2017 | The part from Laubenbachmühle to Mariazell celebrates his 110th annivesary. |
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