The longest railway tunnel in England[128] is the Woodhead or Summit Tunnel of the Manchester, Sheffield and Lincolnshire Railway. Its length is 5,296 yards, or 3 miles and 16 yards, with a gradient of 1 in 200, or 26⅖ feet to the mile, the rise being in the direction from Dunford to Woodhead. The ordinary passenger trains require ten minutes from Dunford to Woodhead, but trains travelling from Woodhead to Dunford take a minute less. Therefore, with the gradient favourable, the speed is only at the rate of 20 miles an hour; against the gradient, 18. It is a single line tunnel.
The Stanedge Tunnel on the Huddersfield Branch of the London and North-Western Railway is exactly 3 miles long, and it is also a single line tunnel; the gradient is nearly a level. The time for passenger trains through it is six minutes, or at the rate of 30 miles an hour; the time for goods trains is nine minutes, or at the rate of 20 miles an hour. The deepest portion of the tunnel is 600 feet below the upper surface of the mountain.
On the 3rd September, 1867, we came through the Shepherd’s Well Tunnel of the London, Chatham and Dover Railway, 2,376 yards long, against the gradient, which is 1 in 100, or 53 feet in the mile for two-thirds of its length, and the remainder nearly level, in two minutes fifteen seconds; on the same day we came through the tunnel in the opposite direction, when the time occupied was one minute forty-two seconds: on the other hand, Mr. Allport, the General Manager of the Midland Railway, to whom we gladly acknowledge ourselves indebted for much valuable information most obligingly afforded, says that the passenger trains are timed to run _in each direction_ through the Dove’s Hole Tunnel 2,420 feet long at the same rate of speed, and actually do run at that speed—nearly 46 miles an hour,—yet the gradient is 1 in 90, or 58⅔ feet per mile. The same for goods trains, their speed is 23 miles an hour in each direction, and Mr. Allport assures us they maintain it in both directions.
The following are the lengths of some of the principal railway tunnels in Great Britain and of the two longest in Ireland:—
Medway South-Eastern 3,740 Sevenoaks ” 3,600 Box Great Western 3,227 Littleborough Lancashire and Yorkshire 2,869 Sapperton Great Western 2,800 Pohhill South Eastern 2,750 Kilsby London and North-Western 2,423 Dove’s Hole Midland 2,420 Shepherd’s Well Chatham and Dover 2,376 Wapping (L’pool) London and North-Western 2,250 Lime Street ” ” 2,230 Clayton London and Brighton 2,200 Sydenham Chatham and Dover 2,190 Abbot’s Cliff South-Eastern 2,000 Watford London and North-Western 1,793 Merstham South-Eastern 1,780 Clay Cross Midland 1,780 Sapperton(A) ” 1,760 Corah Wood Newry and Armagh 1,510 White Ball Bristol and Exeter 1,470 Belsize Midland 1,460 Grenfield Midland 1,400 North-Eastern 1,364 Thackley Midland 1,360 Honiton London and South-Western 1,350 Bletchingly South-Eastern 1,324 Lydgate Lancashire and Yorkshire 1,322 Wichwar Midland 1,320 Shanklin Isle of Wight 1,320 Shakspeare South-Eastern 1,320 Almonsbury Bristol and South Wales 1,320 Kilbarry Great Southern and Western 1,290 Primrose Hill London and North-Western 1,250 Glasgow Edinburgh and Glasgow 1,250 Potter’s Bar Great Northern 1,210 Balcombe London and Brighton 1,122 Brislington (No. 1) Great Western 2,200 Brislington (No. 2) ” 1,100 Brislington (No. 3) ” 330 North Welwyn Great Northern 1,046 Penscliff ” 968 Guildford London and South-Western 965 Saltwood South-Eastern 954 Bangor Chester and Holyhead 910 Chislehurst South Eastern 900 Elstree Midland 900 Gillingham Chatham and Dover 895 Stoke Great Northern 880 Milford Midland 836 Calandar Edinburgh and Glasgow 830 Whitstable South-Eastern 822 Haddon Midland 800 Oakley ” 800 Bishopton Glasgow and South-Western 760 Coates Park Midland 740 Buckhorn Weston Salisbury and Yeovil 739 Belmont Chester and Holyhead 737 Penmaen Bach Chester and Holyhead 721 Tottenham Great Northern 714 Leeds North-Eastern 700 Copenhagen Great Northern 694 Dover Chatham and Dover 682 Manton Midland 660 Ampthill ” 640 Chivet ” 620 Martello South-Eastern 616 Barnet Great Norther 605 Chelsfield South Eastern 600