Disley Tunnel

Disley Tunnel [UK] was built by the Midland Railway in 1902 on its line between New Mills South Junction and Manchester Central, which was more direct than the congested and difficult lines through .

It was the most expensive work on the line and at 2 miles, 346 yards (3,535 m), the second longest tunnel on the Midland system.

By means of a connection on to the old LNWR line from Buxton at Hazel Grove that was opened in 1986, it is now part of the Hope Valley Line into the present-day .

There is also a short (174 yard) Disley Tunnel nearby on the Buxton Line.

The Midland Railway found that with the boom in railway traffic during the last decade of the 19th century the pressure on railway routes was intense with the volume of passenger and goods traffic increasing. This problem was present in all parts of the UK - though the Midlands, especially the Main Line to Manchester and Liverpool, was particularly crowded. The London and North Western Railway and the Great Northern Railway owned the Main Line to Manchester, which meant that the Midland's trains had the lowest priority.

The Midland joined with the Manchester, Sheffield and Lincolnshire Railway company to form the Sheffield and Midland Railway Companies' Committee with the intention of building a "new line" that would bypass the main line, and give priority to their own trains, thus speeding up the service. Various routes were tried, including the "Manchester South District Railway Company" from Heaton Mersey to Chorlton-cum-Hardy. However, congestion continued.

To relieve the congestion through a new line, to be called the "New Mills and Heaton Mersey Railway", was authorised by Act of Parliament in 1898. The plan was to create a railway line that would take four tracks, and most bridges and cuttings were constructed with this width in mind.

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