Middlesex

Middlesex is an area of South East England which was formerly a county; it is now mainly within the ceremonial county of Greater London, with small sections in neighbouring ceremonial counties. The county's boundaries largely followed three rivers: the Thames in the south, the Lea to the east and the Colne to the west. A line of hills formed its northern boundary with Hertfordshire. The county was the second smallest of the historic counties of England, after Rutland.