Classed as one of Isambard Kingdom Brunel's great works, Box Tunnel running under the hill between Corsham and Box, remains famous as a feat of construction and for the history of its construction.
Rail travel was still a novelty when the Great Western Railway line joining London and Bristol was begun. The hill near Box was the last part of the line to be dealt with. It was generally believed that a tunnel through the hill would be so long and deep as to "stifle and deafen" passengers travelling through it.
Brunel was not deterred by such fears and in 1836 work began with the sinking of shafts to determine the course of the tunnel. Initial problems with flooding in parts of some shafts were resolved by the use of a steam pump. The construction was carried on at a great pace with 1500 men initially, rising to 4000 as the final phases were built. Each week a ton of gunpowder and a ton of candles were used up. Work continued twenty-four hours a day with labourers sharing beds in Box and Corsham; "as soon as one lot turned out another lot turned in". The construction work was not without its costs; 100 labours died in accidents while many more were maimed.
The tunnel was opened on 30th June 1841, completing the Great Western Railway mainline. Initially some passengers chose to leave the train before the tunnel and rejoin it the other side, having journeyed round by road. It is a testament to Brunel and his engineers that the Box Tunnel remains a functional element of the London Paddington to Bristol railway line.
Box Tunnel entrance
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