The County of London was a county of England from 1889 to 1965, corresponding to the area today known as Inner London. It was created as part of the general introduction of elected county government in England, by way of the Local Government Act 1888. The Act created an administrative County of London, which included within its territory the City of London. However, the City of London and the County of London formed separate counties for "non-administrative" purposes. The local authority for the county was the London County Council (LCC), who performed initially only a limited range of functions, but gained further powers during its 76 year existence.
http://cityofwestminsterflats.blogspot.com/
