 On its creation in 1965, Greater London was divided into five Commission Areas for justice; that named "Middlesex" consisted of the boroughs of Barnet, Brent, Ealing, Enfield, Haringey, Harrow, Hillingdon and Hounslow.This was abolished on 1 July 2003.The county lies within the London Basin and the most significant feature is the River Thames, which forms the southern boundary.