The London Borough of Brent is a London borough in north west London, and forms part of Outer London. The major areas are Kilburn, Kingsbury, Wembley, Willesden and Harlesden. It borders the boroughs of Harrow to the northwest, Barnet to the northeast, Camden to the east, Westminster to the southeast, and Kensington and Chelsea, Hammersmith and Fulham, and Ealing to the south. Most of the eastern border is formed by the Roman road Watling Street, which is now the modern A5.