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Parliamentary constituency in the United Kingdom, 1950–1983
Runcorn was created for the 1950 general election from parts of several constituencies.
It was abolished following the reorganisation of local authorities in 1974 by the Third Periodic Review of Westminster constituencies for the 1983 general election, when it was divided primarily between the re-established constituency of Eddisbury and the new constituencies of Halton and Warrington South.
From local government boundary changes on 1 April 1974 until the constituency was abolished at the next parliamentary boundary review which came into effect for the 1983 general election, the constituency comprised parts of the expanded Borough of Warrington and the newly formed Borough of Halton, and the District of Vale Royal, but its boundaries were unchanged.
On abolition, the western half of Runcorn was included in the new constituency of Halton along with the town of Widnes (on the northern side of the River Mersey). The eastern half of the town formed part of the Weaver Vale constituency, along with Northwich, Frodsham, Helsby and surrounding areas.