Trolleybuses served the London Passenger Transport Area from 1931 until 1962. For much of its existence, the London system was the largest in the world. It peaked at 68 routes, with a maximum fleet of 1,811 trolleybuses. History London's first 60 trolleybuses were introduced by London United Tramways (LUT), operating from Fulwell bus garage in South-West London. They were nicknamed "Diddlers" and commenced running on . In 1933, LUT was absorbed into the London Passenger Transport Board (LPTB) along with other tram operators, the largest being London County Council (LCC). The LPTB decided to replace all trams with trolleybuses. This started in October 1935, with two more former LUT routes, and continued in stages until June 1940, when World War II caused the suspension of the programme. By then, nearly all the trams North of the River Thames had been replaced, however there were still some 1,100 trams servicing South London. In 1946, a change in policy meant that all remaining tramlines would be replaced by diesel buses. As trolleybuses were bigger than diesel buses (70 seats compared to 56), this meant that more diesel buses were required. It was hoped, however, that this would result in fewer uncollected fares on the smaller vehicles. In 1948, a new batch of 77 trolleybuses replaced the Diddlers, and those which had been destroyed by enemy action. A further 50 new trolleybuses were delivered in 1952 to replace the oldest vehicles, which were then 16 years old. In 1954, it was announced that all trolleybuses were to be replaced by diesel buses, with the exception of the post-war vehicles, which would be retained until about 1970 and run over the original LUT routes. Conversion began in 1959, using AEC Regent III RT buses for the first three stages, and new AEC Routemasters for the remainder. A consortium of Spanish operators bought the post-war vehicles, some of which were converted to motor buses.. The former LUT routes were the last to be converted to diesel buses, on 8 May 1962. Fleet The trolleybuses were designed and built specifically to be worthy tram replacements. Like the trams, they were large high-capacity double deckers, with rapid acceleration. All but one had three axles (necessary as they were 30 feet long), and were much quieter in operation than contemporary trams or diesel buses. Trolleybuses were built on AEC, Leyland and British United Traction chassis. Apart from the