These counties are often referred to as the historic, traditional or former counties. The Local Government Act 1888 created new areas for organising local government that it called administrative counties and county boroughs. These administrative areas adopted the names of, and closely resembled the areas of, the traditional counties.
The greatest change was the creation of the County of London, which was made both an administrative county and a "county"; it included parts of the historic counties of Middlesex, Kent, and Surrey. Other differences were small and resulted from the constraint that urban sanitary districts (and later urban districts and municipal boroughs ) were not permitted to straddle county boundaries.