For many the Routemaster is as much a symbol of London as Big Ben or Tower Bridge.

But while Big Ben's clock tower has not been replaced by a digital clock, and Tower Bridge has not been knocked down to make way for a suspension bridge, the Routemaster's days as a London postcard picture are numbered.

The Mayor of London Ken Livingstone's decision to retire the fleet has been controversial to say the least. Campaigns to save the bus have sprung up across the capital, and Londoners and tourists have pleaded for the old buses to stay in use. Sadly, for the protesters, their pleas have been in vain.

Back in February 1956, the first-ever passenger journey by a Routemaster was made from Golders Green to Crystal Palace, marking the beginning of London's love affair with the unique bus.

The route may have changed today the number 13 travels from Golders Green to Aldwych via landmarks such as Lord's and Trafalgar Square but Friday's final trip can be seen as equally symbolic.

The curvy body and open platform design of the bus combined with the presence of a conductor has made it an iconic image of the capital. It was the last bus to be wholly designed by London Transport and the last to be built with an open platform. Today you are more likely to see a Mercedes articulated bus, or bendy-bus, which have proven prone to spontaneous combustion, than the old Routemaster.

The entire journey from Golders Green to Aldwych Strand is meant to take a mere 45 minutes and with all the hopping on and off passengers are able to do, it can feel like a scenic tour of some of the most picturesque sites of the capital.

On Monday, I decided to take the number 13 for one last journey. As the bus weaved its way up Finchley Road, a group of American tourists on board squealed at the cuteness of that little cottage'. They are referring to the pub that neighbours Swiss Cottage Tube station and some seasoned passengers rolled their eyes. Excitement intensified as Lord's cricket ground in St John's Wood came into view and the Americans hopped off to snap away with their cameras.

As they leave they smile and remark that the routemaster symbolises the UK'.

Travis Elborough, author of The Bus We All Loved, which explores the importance of the Routemaster, is passionate about his subject.

His book tells the story of the Routemaster's invention, its rise and decline, the people who worked on it, and of the enthusiasts who were mad about it.

Describing its enduring appeal, he said: "They offer a sense of the city. They are to London what the gondolas are to Venice, even.

"It is a wonderful way to travel across the city. With the conductor on board, it is like having silver service."

It is the loss of the conductor that many will miss, Mr Elborough said. "We are saying goodbye to the conductors so we have lost the human interaction," he said.

"There is a notion of community in conductors. Some see the same people every day and even remark that they have their regulars. There is something rather special about travelling with one."

This means that figures like Duke Bassey, the harmonica-playing conductor who can be found collecting fares on the 73 route, will also disappear.

Mr Elborough believes the bus portrays the social history of London. "It is a design classic and an iconic image.They can be seen as a classic slice of British modernism.

"Their production was from 1954 to 1968, which were the rock 'n' roll years. Also in 1956, for the first time conductors were recruited directly from Barbados. They changed the landscape of the city. The scheme was then later extended to Jamaica and Trinidad."

It could be said that another positive aspect of having a conductor is simply the option of being able to ask for directions and advice about the city.

Although the 13 does not stop directly outside London Zoo, it does skim near enough for the conductor to tell a mother and her two children how to walk there. As the bus slowed to a halt due to bad traffic, the family were able to simply leap off without having to wait for a bus stop something passengers will not be able to do from Saturday.

To some, the bus is a reminder of a past, but to others it is time to move on. Amy Bell, a passenger who was on her way to Selfridges to do a spot of shopping, said: "I like the bus, it's nice to be able to hop on and off but it is time for a change. They can be quite dangerous and the pollution side of it is something to think about."

Levels of complaints and accidents are higher on the Routemasters than other models, but for many that is a price worth paying. While revolutionary in the 1950s with their light alloy structure, power-assisted steering and power hydraulic brakes, over time the Routemaster has struggled in the face of environmental concerns. The Routemasters' Association argues that Routemasters are durable and adaptable and this means that new generations of engine can be fitted. On its web site, the association declares that they remain among the most technically modern, environmentally sound, fuel-efficient and quickest buses ever to run on London's streets'.

Five years ago, 50 Routemasters were refurbished and Mr Elborough argues that at the time they were the greenest engines around. The overhaul has not, however been enough to save them and the Routemaster has steadily been phased out since August 2003.

Having negotiated its way through the hustle and bustle of consumer-crazed Regents Street and Oxford Circus, we reached historic Trafalgar Square. It seemed a long way from Golders Green, but it is only one bus ride. Two heritage' routes are to be launched in November of this year in an attempt to compensate for the loss. These will cover the main tourist attractions of central London. Mr Elborough said: "I am sad that it will be over.The heritage routes are nice enough but they are for the tourists, not really for the average Londoner just getting around."

For many the streets will never be quite the same again.