Fröndenberg–Kamen railway

The Fröndenberg-Kamen line was built at the turn of the 20th Century as a railway branch line by the Royal railway divisions (German: königliche Eisenbahndirection) of Elberfeld and Essen of the Prussian state railways to connect, in the form of an S-shaped curve, four stations on major east-west routes, which were built in the second half of the 19th century by three competing major private railway companies in Westphalia (from north to south):

• Kamen station on the Dortmund–Hamm line, opened by the Cologne-Minden Railway Company in 1847,
• Unna-Königsborn station on the Welver–Sterkrade line, opened by the Royal Westphalian Railway Company in 1876,
• Unna station on the Dortmund–Soest line, opened by the Bergisch-Märkische Railway Company in 1855,
• Fröndenberg station on the Hagen–Warburg line, also opened by the Bergisch-Märkische Railway Company in 1870.

The first section was opened by the Royal Railway Division of Elberfeld on 2 January 1899 between Fröndenberg and Unna.[2]

The next section from Unna to Unna-Königsborn was a joint project with the Royal Railway Division of Essen and built in just over a year. It was opened on 1 April 1900, originally for freight only.[3]

The last part, from Unna-Königsborn to Kamen was the responsibility of the Essen Division alone. Only half a year later, the line was completed on 1 November 1900 and opened for freight. Almost a year later, on 1 October 1901, the first passenger train ran between Unna and Kamen.[3]

In early 1926, passenger traffic was discontinued on the northern section between Unna and Kamen.[3] The Unna-Kamen-Werne light railway was opened in 1909 on a similar route as an overland tramway (interurban). It closed on 14 December 1950.

On 3 June 1955, freight traffic between Königsborn and Kamen was also discontinued[3] and the line was subsequently dismantled. The former line can easily be identified from aerial photographs.

Electrification of the Unn–Königsborn section was completed on 25 May 1984.[3] The Fröndenberg–Unna section is still a non-electrified branch line with a top speed of 60 km/h. To increase speeds, level crossings are being upgraded. It is served only by the Hönnetal-Bahn (RB 54), which continues over the Letmathe–Fröndenberg line via Menden and the Hönne Valley Railway to Neuenrade at 60-minute intervals.[4]

Prior to the closure of the Westphalian line between Welver and Unna-Königsborn in 1968, passenger services were established on the line between Unna and Unna-Königsborn on 26 May 1963,[3] continuing to Dortmund Stadthaus station.[5]

In 1972 a regular interval regional service was established from Unna via Unna-Königsborn, Dortmund Stadthaus and Dortmund-Dorstfeld to Dortmund-Marten Süd, which was extended in 1983 to Dortmund-Lütgendortmund.[6] This was a direct precursor of line S 4 of the Rhine-Ruhr S-Bahn. In preparation for the S-Bahn, electrification of the line from Unna to Unna-Königsborn was completed on 25 May 1984 and on 28 June 1984 it was upgraded with a top speed of 80 km/h.[3] S-Bahn services commenced on 3 June 1984 and operates at 20-minute intervals.[7]

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  Fröndenberg station
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  Fröndenberg station
• 
  Ardey station
• 
  Former Frömern station building
• 
  Frömern station
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  Unna station before renovation in 2007/2008
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  Unna-Königsborn station
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  Unna-West station
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  Kamen station
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  Kamen station platforms