Claim: London's location is the United Kingdom.

The City of London is a city and county that is an enclave of London . It constituted most of London from its settlement by the Romans in the 1st century AD to the Middle Ages , but the agglomeration has since grown far beyond the City 's borders . The City is now only a tiny part of the metropolis of London , though it remains a notable part of central London . Administratively , it forms one of the 33 local authority districts of Greater London ; however , the City of London is not a London borough , a status reserved for the other 32 districts -LRB- including London 's only other city , the City of Westminster -RRB- .   The City of London is widely referred to simply as the City -LRB- differentiated from the phrase `` the city of London '' by capitalising City -RRB- and is also colloquially known as the Square Mile , as it is 1.12 sqmi in area . Both of these terms are also often used as metonyms for the United Kingdom 's trading and financial services industries , which continue a notable history of being largely based in the City . The name London is now ordinarily used for a far wider area than just the City . London most often denotes the sprawling London metropolis , or the 32 London boroughs , in addition to the City of London itself . This wider usage of London is documented as far back as 1888 , when the County of London was created .   The local authority for the City , namely the City of London Corporation , is unique in the UK and has some unusual responsibilities for a local council , such as being the police authority . It is also unusual in having responsibilities and ownerships beyond its boundaries . The Corporation is headed by the Lord Mayor of the City of London , an office separate from -LRB- and much older than -RRB- the Mayor of London . The current Lord Mayor , as of November 2016 , is Andrew Parmley .   The City is a major business and financial centre . Throughout the 19th century , the City was the world 's primary business centre , and it continues to be a major meeting point for businesses . London came top in the Worldwide Centres of Commerce Index , published in 2008 . The insurance industry is focused around the eastern side of the City , around Lloyd 's building . A secondary financial district exists outside of the City , at Canary Wharf , 2.5 mi to the east .   The City has a resident population of about 7,000 -LRB- 2011 -RRB- but over 300,000 people commute to and work there , mainly in the financial services sector . The legal profession forms a major component of the northern and western sides of the City , especially in the Temple and Chancery Lane areas where the Inns of Court are located , of which two -- Inner Temple and Middle Temple -- fall within the City of London boundary .