LNER Route: Leicester to Marylebone

Catesby Tunnel (Northants)

Catesby tunnel which at 2997 yards, was the longest on the Great Central's route to London, the last of the mainline railways to be built by the Victorians. The Catesby Tunnel was originally planned as a cutting, but due to it running through a wealthy land owners estate, it was insisted that the cutting be turned into a tunnel. The contractor responsible for building this section of the London Extension (Contract No.4, Rugby to Woodford) was T Oliver & Son. At 27 feet wide and 25 feet 6 inches high, Catesby Tunnel is straight throughout and on a rising gradient of 1:176 to the south, with the summit of this section reached as daylight resumes. It was designed as an 'egg shape' tunnel with eight ventilation shafts along its length. It was lined with Staffordshire Blue brick, and over 30 million were used in the 3km length. Its creation demanded round 290,000 cubic yards of mining. Work to sink the first shaft began on 18th February 1895 and the last length was keyed in on 22nd May 1897 - a remarkably quick average rate of 110 yards per month. Progress was greatly accelerated by the use of Ruston steam navvies (cranes). The tunnel was mostly driven from nine construction shafts, each equipped with wooden headgear which was used to lower materials to the men working beneath. None though was permitted within 500 yards of the north portal due to the landowner's wish that the privacy of his residence, close to the workings, be maintained. As a result, 264 yards through very heavy ground had to be constructed by means of a 12x10ft bottom heading and break-ups.

This proved liable to breakages and one part completely collapsed. The surrounding strata was under significant pressure which resulted in a heavy lining of seven rings in the arch and side walls, with six rings in the invert. These were divided into 10-foot sections. Cut-and-cover was used for the first 44 yards from the north portal. The length adjoining this had so little ground above it that the two crown bars were laid from a trench on the surface. The remainder of the tunnel proved relatively light work and was driven full-sized without headings. Here the lining is mostly five rings thick with a four-ring invert, all faced with Staffordshire brindle and built in lime mortar. Around 30 million bricks were swallowed up by the structure. Very little water ingress was experienced, amounting to around 80 gallons per minute. Chases were built into the back of the brickwork at intervals, leading to pipes built through the side wall at rail level. Water was then discharged into a culvert in the six-foot, accessed via deep catchpits. Ventilation is provided by five shafts. Four of these are 10 feet in diameter but the northernmost - 1,250 yards from the entrance - is 15 feet wide to provide greater air flow. The landowner did not want his view blighted by rising smoke either! The first belch from coal traffic occurred on 25th July 1898.

Trackworkers were relatively well served with regular refuges provided on both sides and three rest cabins built into the Up side wall. One is located directly opposite the tablet that marks the "half way" point. Both lines through the tunnel were inspected by the local ganger twice each day. In the winter of 1906, this role was carried out by Joseph Turner, as it had been for the previous 18 months. At about 4:20pm on 4th January he completed an examination of the Down line. Half-an-hour later, a London-Manchester express with upwards of 50 passengers on board entered the south end of the tunnel at around 60mph. As it approached the fifth shaft, a rail broke beneath the locomotive and all five coaches behind it derailed, ripping up 450 yards of track. The last carriage became detached and came to a stand foul of the adjacent Up line as a goods train was approaching. Only prompt action by the driver, who put down a detonator, and the guard, who sounded the whistle, prevented a collision. The report on the derailment of the passenger train in Catesby Tunnel can be seen here courtesy of the Railways Archive website. Catesby Tunnel retired from operational service on 3rd September 1966 since which time the permanent way has been removed.