Hendon was an ancient civil parish of around 8,250 acres (33 km2) which included Mill Hill on the border of Hertfordshire, as well as Golders Green and Childs Hill on the border of what became the County of London. In 1894 it was created an urban district of Middlesex and in 1932 it became a municipal borough. The municipal borough was abolished in 1965 and the area became part of the London Borough of Barnet.