Twickenham is a town in south west London on the River Thames in the London Borough of Richmond upon Thames, located southwest of the centre of London. The administrative headquarters of the borough are at York House in Twickenham, which is of equal importance to Richmond in the London Plan. It expanded rapidly during the suburban growth of London from 1881 until 1961, when its population grew and its farms and common were converted to other use. In 1926 it was incorporated as the Municipal Borough of Twickenham, which merged into the present Greater London borough in 1965.