Middlesex (MDX), England
Location and Adjacent Counties
Historic Middlesex, prior to 1889, was bordered on the east by Essex, to the south east by The City of London, to the south west by Surrey, to the west by Buckinghamshire and to the north by Hertfordshire.Middlesex does not have a single established historic county town, because of the proximity and the dominance of London.
For additional information see Wikipedia and GENUKI:Middlesex