The Mersey Railway was the passenger railway connecting the communities of Liverpool and Birkenhead, England. It is currently a part of the Merseyrail network. It was extended further into the Wirral Peninsula, which lies on the opposite bank of the River Mersey to Liverpool. Both sides of the river were connected via the Mersey Railway Tunnel. The railway opened in 1886 with four stations using steam locomotives hauling unheated wooden carriages; in the next six years the line was extended with the opening of three more stations. Using the first tunnel under the Mersey, the line is the world's oldest underground railway outside London.
Because the steam locomotives created a polluted atmosphere in the tunnel despite the forced ventilation system, many passengers reverted back to using the river ferries making the railway bankrupt by 1900. Recovery came after the railway adopted electric traction in 1903. The Mersey Railway remained independent after the railway grouping of 1923, although it became closely integrated with the electric train services operated by the London, Midland and Scottish Railway over the former Wirral Railway routes after 1938. The Mersey Railway was nationalised, along with most other British railway companies, in 1948.
