From London Midland & Scottish Railway Collection. Train approaching Watford tunnel, Hertfordshire, about 1840.
Watford tunnel was opened in 1838, and was on the London & Birmingham Railway, later amalgamated into the London & North Western Railway, then the London, Midland & Scottish Railway.
Building tunnels was extremely dangerous work. Navvies were killed and injured by falling rocks or earth, and in explosions caused by gunpowder used to loosen the earth and rock.
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