outer borough of London, forming part of its western perimeter. Hillingdon belongs to the historic county of Middlesex. Hillingdon was created a borough in 1965 by the amalgamation of the former borough of Uxbridge with the urban districts of Hayes and Harlington, Ruislip-Northwood, and Yiewsley and West Drayton. It includes the historic villages and areas of (roughly from north to south) Northwood, Harefield, Eastcote, Ruislip, Ickenham, South Ruislip, Uxbridge, Hillingdon, Cowley, Hayes End, Yeading, Hayes, Yiewsley, West Drayton, Sipson, Harlington, Harmondsworth, Sipson Green, and Heathrow.
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