There have been a considerable number of small changes to the Greater London boundary since its creation in 1965. The most significant of these were the 1969 transfers of Knockholt to Kent and Farleigh to Surrey and a series of minor adjustments during the 1990s which realigned the boundary to the M25 motorway in some places.
In 2004, following a poll, a move was mooted by the London Assembly to entirely align the Greater London boundary to the M25 motorway.London Assembly - . 2 March 2004. Retrieved on 23 February 2008. The Mayor of London suggested in 2005 that Dartford, Thurrock and Watford could be given the opportunity to vote on inclusion in Greater London in local referendums. In 2010 it was suggested that an extension of the boundary to include Elmbridge was being considered.