City of London
The City of London is a city in Middlesex that lies at the heart of, and is distinct from, London. It forms the administrative county of the City of London Corporation and is also a county for the purposes of lieutenancy. It has a population of just 9,200 (2005 est) and an area of 1 sq mile (2.6 km2) but is a highly important district as it encompasses most of London's main financial institutions; indeed, the term 'the City' is often used to describe the UK financial sector (as is another term, 'the square mile', referring to the area of the City). This usage has, confusingly, continued even though a significant proportion of the financial sector is now based in Canary Wharf, several miles out from the City.
From the sixteenth century onwards London began to expand rapidly in all directions, while the Corporation of the City of London continued to rule just over its original domain; from the nineteenth century it began to adopt its special financial character, and its population began to drop steeply. Today, in terms of population, it is the second smallest of English cities, and while scores of thousands of workers travel to the City daily, on Sundays its deserted streets feel like those of a remarkably opulent ghost town.
The City of Westminster, the other major historical heart of London, is located west of the City of London.
City of London Corporation
The City of London Corporation, officially Mayor and Commonalty and Citizens of the City of London, is the local authority responsible for local government in the City of London, with its functions being effectively identical to those of the London borough councils and unitary authorities elsewhere in England.