History: London, England, United Kingdom

Geography
Scope
Greater London is the top-level administrative subdivision covering London. The small, ancient City of London at its core once contained the whole settlement, but as the urban area grew the City Corporation resisted attempts to amalgamate it with its suburbs, causing "London" to be defined in a number ways for different purposes; and the situation was once open to legal debate. Forty per cent of Greater London is covered by the London post town, within which 'LONDON' forms part of postal addresses.
The London telephone area code (020) covers a larger area, similar in size to Greater London, although some outer districts are omitted and some places just outside are included. The area within the orbital M25 motorway is normally what is referred to as 'London'. and the Greater London boundary has been aligned to it in places.