Snow Hill tunnel

Snow Hill Tunnel is a railway tunnel on the northern edge of the City of London which carries the up and down Snow Hill lines between City Thameslink and Farringdon stations. The tunnel runs beneath the Smithfield meat market and was constructed, using the cut-and-cover method, immediately prior to the building of the market. The tunnel opened on 1 January 1866.

Snow Hill tunnel was constructed by the London, Chatham and Dover Railway to connect its line from Herne Hill to the recently-opened Metropolitan Railway's Widened Lines, south of Farringdon station. To the north-west, the Widened Lines in turn connected to the tracks of the Great Northern Railway at King's Cross, and the Midland Railway at St Pancras, via tunnels running beneath the two main line termini. Snow Hill tunnel thus provided the crucial link in the only north-south railway route through central London, enabling a number of main line railway companies to run cross-London passenger and goods services.

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