區域線
On 4 July 1932, the Piccadilly line was extended west from its original terminus at Hammersmith and shared the route with the District line to Ealing Common. From Ealing Common to South Harrow, the District line was replaced by the Piccadilly line, and from that date, District line trains from Acton Town ran only either to Hounslow West or to Ealing Broadway. On 9 January 1933 Piccadilly line trains, sharing with the District line, began serving Northfields on the Hounslow branch, and their service was extended to Hounslow West on 13 March 1933 but Piccadilly line trains did not call at South Ealing until 1935. District line services on the Hounslow branch were withdrawn on 9 and 10 October 1964 after which operations were provided by the Piccadilly line alone.