THEY were once a familiar sight on the busy streets of the capital.

But an estimated 1,600 people converged on Carlton Colville at the weekend for a record-breaking two-day event that celebrated a fondly-remembered part of London's public transport heritage.

The East Anglia Transport Museum displayed and operated eight London trolleybuses on Sunday and Monday to mark the 50th anniversary of when they stopped trundling along the capital's streets. Among the venerable electric-powered vehicles was London's very first trolleybus, known as the Diddler, from 1931.

There were long queues to get into the museum as 800 people visited on both days – many of them taking the chance of a nostalgic ride on the trolleybuses, which fell out of favour in 1962 because of the cost of electricity and lower prices for diesel and petrol. They last took passengers around London on May 9, 1962.

The museum took two years to set up the event, which was the largest gathering of existing London trolleybuses in recent years and which, organisers admitted, would probably not happen again.

Four of the vehicles are from the museum and the other four came from museums in London and Yorkshire.

Ken Blacker, secretary of the transport museum, said visitor numbers during the two days had been 'phenomenal' as they normally received 16,000 visits over their entire April-September season.

As well as the estimated 1,600 weekend visitors, another 400 transport enthusiasts had visited the charitably-run museum to view the trolleybuses on pre-arranged trips before the public days.

Mr Blacker told The Journal: 'I think we can say that we have got record-breaking visitor numbers for two days. I think it has been a success because of the nostalgic value of the trolleybus.'

He added: 'Trolleybuses were quiet, very fast and very ecologically friendly. Other countries could see their benefits and kept them.... Sadly they fell out of favour for two reasons: diesel and oil became cheaper after the war and in the same period electricity was also nationalised and after that prices for electricity went up tremendously.'

In Britain the last trolleybus in public service stopped running in Bradford in 1972.

Among those visiting on Monday were Katy and Clifford Lee, from Bungay, and their sons Jasper, four, and Xavier, two. Mrs Lee said: 'The boys have loved coming here. We have all signed up today for a season ticket.

'They do a wonderful job here at the museum and the trolleybuses were great – the boys loved them.'

The event also marked another notable milestone for London – the 60th anniversary of trams ceasing operation in the capital. To reflect this, the museum also ran its 1858 London tram over the two days.

? For more on the East Anglia Transport Museum, visit: www.eatm.org.uk