Copenhagen Tunnel
 Copenhagen Tunnel southern portals | |
| Overview | |
|---|---|
| Line | East Coast Main Line |
| Location | Barnsbury |
| Coordinates | 51°32′45″N 0°07′14″W / 51.5457°N 0.1206°W |
| OS grid reference | TQ 30404 84602 |
| Status |
|
| System | National Rail |
| Start |
|
| Operation | |
| Owner | Network Rail |
| Operator | Great Northern LNER |
| Technical | |
| Design engineer | Thomas Brassey |
| Length | 594 yd (543 m) |
| No. of tracks | 4 (6 until 1977) |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in) |
| Electrified | 25 kV 50 Hz AC |
The Copenhagen Tunnel is a railway tunnel in London, United Kingdom, that is situated approximately 0.8 miles (1.3 km) down the East Coast Main Line from London King's Cross railway station. It comprises three twin-track bores, of which only the central and western have been in use since the remodelling of Kings Cross in 1977.
Design
[edit]_north_portals.jpg)
The tunnel consists of two operational parallel bores, officially named the Centre Bore, which carries the fast lines, and the West Bore, which carries the slow lines. Both bores are 594 yards (543 m) in length and are situated 0 miles 65 chains (0.81 miles, 1.31 km) to 1 mile 12 chains (1.15 miles, 1.85 km) from London King's Cross railway station, where mileage on the East Coast Main Line is measured from.[1]
The speed limit in the western bore is 40 miles per hour (64 km/h) on both lines for passenger and empty stock trains; it is only 25 miles per hour (40 km/h) for other trains in the down direction. The speed limit in the central bore is 60 miles per hour (97 km/h) on both lines for passenger and empty stock trains; it is only 35 miles per hour (56 km/h) for other trains in the up direction.[2] The tunnel has a steep ascending gradient of 1 in 110 (0.91%),[3] which historically led to operation complexities.[4]
Both tunnels contain a facing point, with a speed limit of 60 miles per hour (97 km/h) in the central bore and 40 miles per hour (64 km/h) in the western bore. The point in the western bore must be used by trains to allow bidirectional access to the chord that connects the East Coast Main Line to the North London Incline,[2] which allows access to the North London line and the High Speed 1 section of St Pancras railway station.[5]
At its southern end, the tunnel is immediately preceded by Holloway Junction, which is where the line transitions from being quadrupled by direction to quadrupled by speed by means of the Up Slow line transversing a flyover over the two fast lines (see photo).[2] After this, the railway begins to ascend at a rate of 1 in 200 (0.5%) until Potters Bar railway station.[3]
History
[edit]Construction and opening
[edit]
The Copenhagen Tunnel marked the end of Thomas Brassey's contract on the Great Northern Railway, and once the contract was awarded to Pearce and Smith it meant that the entire line was accounted for except for King's Cross station itself.[7][8] The first of the multiple tunnels was built as part of the construction of the Great Northern Railway and was opened in 1850. This section of the railway was designed by the engineer Thomas Brassey and was built by Pearce and Smith and John Jay.
The name is taken from Copenhagen Fields, an open space directly above the tunnels, that was once the location of the Ambassador of Denmark's residence in the 17th century. This became a popular pleasure garden and was a public meeting area, notable for rioting there in the late 18th century.[9][6] From this site on 21 April 1834 thousands marched in support of The Tolpuddle Martyrs who had been sentenced to transportation to Australia for forming a trade union.[10] Market Road Gardens, an open space directly above the tunnels, are a present-day surviving remnant of the Fields.
Pearce and Smith were contracted to build the tunnel, and made the bricks on site using innovative techniques that were new in London at the time. Their first attempt involved using clay and sand but not any ash, which led to hard but brittle bricks that cracked in the kiln. Their improved method involved processing the clay immediately after it was dug out before slop-moulding it into shape having been combined with ash.[11] The kilns that the bricks were burnt in were coal-fuelled and exposed, which led the bricks to have an unusually red colour but did not affect their efficacy. To save money, Pearce and Smith also sometimes used sawdust rather than sand which was supplied by a sawmill. They also used a single steam engine to power the mortar mill, lifts in the tunnel shafts, and the sawmill.[11]
Operation
[edit]
It was at Copenhagen Tunnel where passenger services from King's Cross via the Gasworks Tunnel met goods trains and coal trains from expansive depots situated north of the Regent's Canal.[4] The western tracks north of the tunnel also had a former connection to the lines serving King's Cross Goods Yard, which connected at Goods and Mineral Junction and its corresponding signal box. The two lines in the Western bore were formerly named the Up Goods and Down Goods for this reason, and also because all three bores were still in situ.[12]
To those who have had no opportunities of seeing the processes in the Midland districts, a visit to the Copenhagen Tunnel works will be full of interest; and, amongst other novelties, may be mentioned the use of saw-dust in lieu of sand*, the latter material being very costly, whilst the former is supplied on the works from a saw-mill worked by a steam-engine, which at the same time drives the mortar-mill, and works the lifts at two of the tunnel shafts.[11]
The area above the southern tunnel portal was used for a rail line going to the Caledonian Road Coal and Goods Depot (now Bunning Way) which passed along the parapet of the tunnel entrance. This was situated conveniently close to the Metropolitan Cattle Market, located on the ground above the tunnels from 1855 to 1963. Many trains carried cattle along this line on their last journey to the abattoirs there.[13]
The original tunnel is now the middle of three parallel bores. A second tunnel to the west was built in 1877 and a third one to the east in 1886. The western bore carried up and down goods traffic, the central one was used for down passenger traffic and the eastern bore was used for up passenger traffic. Following electrification in the 1970s, the layout was remodelled, as Kings Cross Goods Yard and Top Shed had closed so it was possible to remove the goods lines and simplify the track layout. The eastern tunnel was taken out of railway service but maintained to ensure the integrity of the ground overhead – it provides road vehicle access to Holloway Bank.[14]
In the 1955 British film comedy The Ladykillers, the northern portal of the tunnel is used as a set for the disposal of the body of Cecil Parker behind the house of Mrs Wilberforce, which was a set created over the tunnel specifically for the film.[15][16]
In January 2024, the Copenhagen Tunnel and the neighbouring Gasworks Tunnel became the first in the country to have new signal-boosting technology fitted inside. This stops devices from losing signal and allows passengers to continue calls while travelling through the tunnels. The upgrade was funded entirely by London North Eastern Railway.[17]
See also
[edit]
References
[edit]- ^ "London North Eastern Sectional Appendix" (PDF). National Electronic Sectional Appendix. Network Rail. p. 201. 7 June 2025. Retrieved 27 June 2025.
- ^ a b c "London North Eastern Sectional Appendix" (PDF). National Electronic Sectional Appendix. Network Rail. p. 200. 7 June 2025. Retrieved 27 June 2025.
- ^ a b "Mr Stirling's New Engines, Great Northern Railway". The Engineer. 32: 211. 29 September 1871 – via Google Books.
- ^ a b Nilsen, M. (2008). Railways and the Western European Capitals. Springer. pp. 57–58. ISBN 978-0-230-61577-9 – via Google Books.
- ^ "London North Eastern Sectional Appendix" (PDF). National Electronic Sectional Appendix. Network Rail. p. 232. 7 June 2025. Retrieved 27 June 2025.
- ^ a b Copenhagen Fields The Model Railway Club, Accessed December 2014.
- ^ "Great Northern Railway". Herepath's Railway Journal. 11 (510): 285. 17 March 1849 – via Google Books.
- ^ "Railway Jottings". The Builder. 7 (322): 164. 7 April 1849 – via Google Books.
- ^ Copenhagen, Islington Hidden London, Accessed December 2014.
- ^ Plaque: Tolpuddle Martyrs at Copenhagen Fields 2014 London Remembers. Accessed December 2014.
- ^ a b c Dobson, Edward (1850). A Rudimentary Treatise on the Manufacture of Bricks and Tiles. London: John Weale. pp. 45–46 – via Google Books.
- ^ Tuffrey, Peter; Brooksbank, B. W. L. (2022). "King's Cross to Hitchin". The East Coast Main Line 1939–1959. Vol. 2. Fonthill Media – via Google Books.
- ^ Caledonian Road Goods Depot The LNER Encyclopedia, December 2005, Accessed December 2014
- ^ "KING'S CROSS REMODELLING MOVES FORWARD". www.modernrailways.com. 14 July 2023. Retrieved 30 June 2025.
- ^ "The Ladykillers film locations". Movie Locations. Archived from the original on 17 May 2018. Retrieved 30 June 2025.
- ^ "THE LADYKILLERS". British Railway Movie Database. Archived from the original on 25 July 2024. Retrieved 30 June 2025.
- ^ "King's Cross mobile 'breakthrough' will keep passengers connected". Rail Magazine. Retrieved 27 June 2025.