The London Borough of Ealing is a London Borough in west London, England, and forms a part of Outer London. The London borough was formed in 1965 by the merging the area of the Municipal Borough of Ealing, the Municipal Borough of Southall along with the Municipal Borough of Acton. The London Borough of Ealing borders the London Borough of Hillingdon to the west, the London Borough of Harrow and the London Borough of Brent to the north, the London Borough of Hammersmith and Fulham to the east and the London Borough of Hounslow to the south. It covers a total area of about 21.44 square miles.
As recorded in population estimates from the middle of 2014, the borough has a permanent population of around 342118 inhabitants. This makes it the third biggest London Borough in population, and 11th largest in size, covering a part of west London along with a small a part of northwest London. The local authority is Ealing London Borough Council.
The town is served by several National Rail and London Underground stations. In conjunction with Brentford, the London Borough of Ealing is the setting for much of the action in Robert Rankin's trilogy comedic novels, The Brentford Trilogy, which currently consists of six volumes. Ealing is also the primary setting for 'The Sarah Jane Adventures', being the location of Sarah Jane Smith's residence. 330 hectares within the borough are designated as part of the Metropolitan Green Belt.