The Cowburn Tunnel is a railway tunnel at the western end of the Vale of Edale

Edale

Edale is a small Derbyshire village and Civil parish in the Peak District, in the Midlands of England. The Parish of Edale,area ,is in the Borough of High Peak....

 in the Derbyshire

Derbyshire

Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...

 Peak District

Peak District

The Peak District is an upland area in central and northern England, lying mainly in northern Derbyshire, but also covering parts of Cheshire, Greater Manchester, Staffordshire, and South and West Yorkshire....

 of England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

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The tunnel is 3702 yards (3,385 m) long. It was built in 1891 by the Midland Railway

Midland Railway

The Midland Railway was a railway company in the United Kingdom from 1844 to 1922, when it became part of the London, Midland and Scottish Railway....

, under Colborne (part of a 1700 ft (518 m) moorland between Kinder Scout

Kinder Scout

Kinder Scout is a moorland plateau in the Dark Peak of the Derbyshire Peak District in England. Part of the moor, at 636 m above sea level, is the highest point in the Peak District, the highest point in Derbyshire, and the highest point in the East Midlands. It is accessible from the villages of...

 and Rushup Edge

Mam Tor

Mam Tor is a hill near Castleton in the High Peak of Derbyshire, England. Its name literally translates as Heights of the Mother and it is also known as the Shivering Mountain on account of the instability of its lower shale layers...

). It takes the Hope Valley Line

Hope Valley Line

The Hope Valley Line is a railway line in England linking Sheffield with Manchester. It was completed in 1894.From Sheffield, trains head down the Midland Main Line to Dore, where the Hope Valley Line branches off to run through the Totley Tunnel .It emerges in the stunning scenery of the Hope...

 west out of Edale valley, to emerge near Chinley

Chinley

Chinley is a rural village in High Peak Borough, situated on the western edge of the Peak District National Park in Derbyshire, England, with a population of around 2000. Before the railway, the area was economically dominated by agriculture and quarrying. Three textile mills were established in...

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Unusually, the tunnel is not built at a constant gradient: in fact, the summit of the line between Dore

Dore

Dore is a village in South Yorkshire, England. The village lies on a hill above the River Sheaf, and until 1934 was part of Derbyshire, but it is now a suburb of Sheffield. It is served by Dore and Totley railway station on the Hope Valley Line...

 and Chinley lies within the tunnel, about a quarter of the way from the eastern end. From the summit, the tunnel falls at 1 in 100 (1%) eastwards and 1 in 150 (0.67%) westwards. Nevertheless, when the headings met, they were no more than 1 inches (25.4 mm) out of line in the vertical direction, and met exactly in the horizontal direction. Only one vertical shaft was used. Although the workings were much drier than they had been for Totley Tunnel

Totley Tunnel

Totley Tunnel is a tunnel on the former Midland Railway Manchester-Sheffield line between Totley on the outskirts of Sheffield and Grindleford in Derbyshire, England. It was completed in 1893 and was the longest mainline railway tunnel within the United Kingdom that ran under land for its entire...

, on one occasion the headings filled with water to a depth of 90 ft (27.4 m) and work was carried on in a diving bell

Diving bell

A diving bell is a rigid chamber used to transport divers to depth in the ocean. The most common types are the wet bell and the closed bell....

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