Middlesex was an administrative area in England, mostly covered by Greater London. It was one of the 39 historical counties of England. It included the City of London, which was self-governing from the thirteenth century.
Middlesex has not existed administratively since 1965 when it was mostly subsumed into Greater London. Although it remains in use as a postal county, and is still used informally as an area name.
The name means the territory of the middle Saxons and its first recorded use was in A.D 704 as Middleseaxan.
Middlesex was recorded in the Domesday Book as being divided into the six hundreds of Edmonton , Elthorne , Gore , Hounslow (later Isleworth ), Ossulstone and Spelthorne.
London's northwestern suburbs steadily covered large parts of Middlesex, especially following the coming of the railways. In 1888 much of the area became part of the County of London - the present-day boroughs of Camden, Hackney, Hammersmith and Fulham, Kensington and Chelsea, Islington, Tower Hamlets and Westminster were removed.
During the next few decades the county became almost entirely urbanised by suburbs of London. Towards the end of the period, many of the boroughs in the area were demanding independence from Middlesex County Council as county boroughs, which if granted would have left Middlesex County Council controlling an area with three distinct and unconnected fragments - in the west, the south-east and the north of the county.
Instead, in 1965, nearly all the remainder of Middlesex was subsumed by the new Greater London except the Potters Bar district, which was ceded to Hertfordshire, and the district of Spelthorne, which was ceded to Surrey. The greater part went to form the new London boroughs of Barnet (part only), Brent, Ealing, Enfield, Haringey, Harrow, Hillingdon, Hounslow and Richmond (part only).
In 1995 the village of Poyle was transferred from Spelthorne in Surrey to the Berkshire borough of Slough.
Middlesex is still used as a placename popularly and by the Royal Mail, and exists in the name of such organisations as the Middlesex County Cricket Club or Middlesex University. Royal Mail guidelines now leave the use on letters of the historic county, administrative county, or no county at all up to the personal preference of the addresser, and Middlesex is consequently commonly found on addresses outside the London postal districts (and sometimes, even within). From an organisational point of view the Royal Mail does however recognise the existence of an area called Middlesex as one of the postal counties of England, but confusingly it is not identical to the historic county boundaries - not only have large sections formed part of the London postal district but elsewhere the borders occasionally follow a different course, such as the village of Denham which is in both the traditional and administrative county of Buckinghamshire but in the postal county of Middlesex (short form Middx).
The River Thames, River Lee and the Rover Colne are all boundaries of Middlesex. In the area around Richmond upon Thames and Twickenham, one bank of the River Thames is often referred to as the "Middlesex Bank", with "Surrey Bank" for the opposite side of the river - this identification is especially useful where the river flows in a north-westerly direction, thus making the terms "north bank" and "south bank" somewhat confusing.
The town of Staines, for instance, is north of the River Thames but is now located, administratively if not postally or in the minds of its residents, in Surrey.
The highest point is the High Road in Bushey Heath at 504 feet.
Places once part of the county are:
Places of interest
Middlesex in its final form consisted of the following districts