The Greenford branch line is a Network Rail suburban railway line in west London, England. It runs northerly from a triangular junction with the Great Western Main Line west of West Ealing to a central bay platform at Greenford station, where it has cross-platform interchanges to the London Underground's Central line. A triangular junction near Greenford connects to the Acton–Northolt line (formerly the New North Main Line). The line serves mainly the suburbs of Ealing and Greenford. History The opening of the line in 1903 coincided with the opening of a station at Park Royal on the Acton–Northolt line to serve the Royal Agricultural Show held in the grounds of part of the Twyford Abbey Estate. The Show ran from 15 June 1903 to 4 July 1903 during which period trains operated a circular service to and from Paddington via Park Royal and Ealing. Normal services started on 2 May 1904 and the links to Greenford station were put in on 1 October 1904. The loop formed by the GWML, the branch and the ANL is sometimes used for turning trains for operational reasons such as balancing wheel wear. On weekends in 2008 during engineering works on the West Coast Main Line the line was used by Virgin Trains' Euston-Birmingham International "Blockade Buster" service which ran to Euston via Willesden, Acton Main Line, Ealing Broadway, Greenford, High Wycombe, Banbury and Coventry using pairs of 5-car Voyager sets. On two Sundays in February 2010, Chiltern and Wrexham & Shropshire trains were diverted to Paddington via the line while engineering work blocked the route to Marylebone. Locally the service is called the 'Push-and-pull', a term which dates from the days of steam, when the engine could not change ends at Greenford and so the locomotive pulled the carriages one way and pushed them on the return run (see GWR Autocoach). In the 1950s the service frequently ran with two auto-trailers, one either side of the engine. During the 1960s and '70s the service was normally operated by a 'Bubble Car' two-carriage diesel railcar, although this was later reduced to a single carriage. As , and have short platforms the maximum length of train that can be used is two cars. In preparation for Crossrail, a new platform 5 has been constructed at West Ealing, and most services now terminate there. In February 2022, GWR announced plans to test fast-charge battery technology on