List of county exclaves in England and Wales 1844 - 1974

Until 1844, many of the counties in England and Wales had exclaves or detached parts, entirely surrounded by other counties. The Counties (Detached Parts) Act 1844 resulted in many of these exclaves being absorbed by the county in which they were locally situated. Nevertheless, a number of exclaves remained; which were dealt with in a piecemeal manner over a period of decades.

The Local Government Act 1894 empowered the county councils of administrative counties to exchange areas in order to make a more effective local government area. As the Local Government Act 1888 had redefined the lieutenancy and shrievalty to be based on administrative counties, the changes also affected them as well as judicial boundaries. Accordingly, many anomalies in county boundaries were removed in the next three years, including the elimination of outlying areas of Derbyshire and Huntingdonshire.

The last major transfer of areas was in 1931, when the boundaries of Gloucestershire, Warwickshire and Worcestershire were realigned. Following the creation of a new administrative county of Huntingdon and Peterborough in 1965, and boundary changes at Dudley in 1966, Flintshire was left as the only county with detached areas — these remained right up to the abolition of the county council in 1974.

The detached parish of Llysfaen was transferred to Denbighshire and the urban district of Colwyn Bay in 1923.

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