A long-established motor bus route serving Isleworth (and Hounslow) was the number 37. This was one of the earliest motor bus routes introduced by the London General Omnibus Company and it originally ran from Isleworth to Peckham via St Margarets, Richmond, Barnes, Putney, Wandsworth, Clapham Junction, Clapham Common, Brixton, Herne Hill and East Dulwich. It was later extended westward to Hounslow (going round the back streets to avoid the low railway bridge in St John's Road and to serve Isleworth railway station) and for a brief time in the 1920s offered a summer Sunday service extension as far as Maidenhead. Even without that short-lived extension the 37 was one of London's longest routes. Between 1922 and 1938 its western terminus was the "Hussar" at Hounslow Heath but was then cut back to turn at Hounslow Bus Garage (later Bus Station). At the beginning the terminus in Isleworth was the forecourt of the Northumberland Arms public house and the destination boards displayed "ISLEWORTH Market Place". Later, for "short" journeys, this was changed to stands in Magdala Road and then in South Street, outside the Public Hall. In 1991 this historic route was curtailed to run between Peckham and Putney, and the section between Richmond and Hounslow via Isleworth became a new, more localised service numbered H37.