In Bordeaux, only trams and cyclists enjoy free passage into the heart of the city, writes Frank McDonald

The honey-coloured sandstone buildings of Bordeaux are gleaming now, and the main public spaces of the city are filled with people. But not much more than 10 years ago, most of the buildings were blackened by pollution and the streets and squares were choked with traffic. Bordeaux had become "la ville noir". It took the current mayor, Alain Juppé, to get to grips with it. In 1995, he scrapped his long-serving predecessor Jacques Chaban-Delmas's plans for a metro, in favour of a street-running tramway, and decided to turn the quays of the Garonne river into a public promenade instead of sacrificing them for up to 18 traffic lanes.

With the breakneck speed of French planning, the first tram line opened in 2003, and by July 2004, a 25km network of three lines - all of which connect up, needless to say - was in place. A second phase, extending all three lines by a total of 19km, is already under way and will be fully operational by the end of next year.

"Every four months, we will open a new extension," Xavier Tersen of Veolia Transport confidently tells us. Veolia also operates the Luas in Dublin, but the tramway in Bordeaux is in a different league. Amazingly, it has no overhead power lines in the city centre; trams are energised by a third rail on the track bed as they pass over it.

There was a political will to protect the city's patrimoine (heritage) - indeed, a demand by the French ministry of culture that this be done. So Alstom, which manufactured the trams in La Rochelle - where the Luas vehicles were also made - came up with the "world first" of activating the electric power by radio signal.

"There is no danger [ to pedestrians] because the electricity moves with the wagon," Tersen says. In the beginning, he concedes, there were technical problems, but these have since been ironed out. Jointed frameworks on the trams slide down and fit nearly into their roofs when not in use.

From the outset, all of the city's bus routes were reorganised to integrate with the tramway. This was much easier than in Dublin because Veolia runs the trams and the buses in Bordeaux. Ticketing is also integrated, with a cheap flat fare of €1.30 that's valid for any journey within an hour of purchase.

A fourth tramline is now being planned, and it is expected that the overall cost of the entire 44km network will be €1 billion - "much cheaper than a nuclear power station", as Tersen says. It will also work out a lot cheaper than the Luas, which cost €750 million for just 26km - the Red and Green lines, which don't even link up yet.

The tramway was developed by Communauté Urbaine de Bordeaux (CUB), a federation of municipalities in the greater Bordeaux area, which has a population of 670,000. CUB has financed 60 per cent of the cost, with the rest coming from a 1.6 per cent payroll tax levied on all companies in the region with nine or more staff.

Bus and tram services carry 300,000 passengers per day, and their operation is subsidised by CUB, which accounts for the flat fare. The tramway carries 55 per cent of the total number of passengers and, Tersen says, covers 95 per cent of its running costs; it is the buses, all of which are now gas-powered, that need the subsidy.

Bordeaux's trams, with their black, grey and blue livery, are more elegant than Luas vehicles, and seem almost to float through the city's streets. Most of them are longer, too (44m), though on one less-intensively used line they are 33m long - three metres longer than the congested trams on the Tallaght line.

The tramway was also treated as a "complete urban project". Before its introduction, Bordeaux had just one pedestrianised shopping street (rue St Catherine) and the city's cathedral was marooned on a traffic island. Now, cars are banned from the historic core, and the Place Bey in front of the cathedral is a pedestrian plaza.

There is access for delivery vehicles and cars with permits. Barriers such as those used in multi-storey car parks prevent access at key points. If motorists want to get in, they have to use an intercom to get permission from the police; only trams and cyclists enjoy free passage into the heart of the city.

Traffic on the quays has been reduced to four lanes, to make room for a wide promenade along the Garonne designed by Parisian landscape architect Michel Corajoud. It includes a beautiful rectangular water feature, the Miroir d'Eau, which reflects the facades of Place de la Bourse at night and sprays mist during the day.

THE RESULTS HAVE BEEN dramatic, according to Michel Duchène, deputy mayor of Bordeaux. "Traffic in the heart of the city is down by 35 per cent, we have seen an explosion in the use of bicycles and there are now 30,000 more inhabitants in the city," he says. "The key project in realising all of this was the tramway."

It was, as Duchène puts it, a "political project" designed to protect the historic core and achieve a new balance between people and traffic. Shopkeepers were "the most aggressive" in opposing it, believing that they would lose business if cars were not let in, but in the end more shops moved back to the city centre.

"People have taken possession of the city and made it their own," he says. Underground car parks for short-term use were installed under some squares and motorists using a park-and-ride site on the outskirts to take a tram into town can park all day for free. The city also bought 4,000 bicycles to promote more cycling.

Since 1995, owners of historic buildings have been obliged to clean them (usually by laser treatment), turning "la ville noir" into "la ville blonde". As a quid pro quo, the city made a commitment to upgrade streets and squares, using remarkably high-quality stone paving. So it's no wonder Unesco was impressed.

Mayor Alain Juppé, who was re-elected in 2005 (though he lost his parliamentary seat in the recent French general election), describes what has happened in Bordeaux as a "renaissance" and modestly agrees that it needed political will to overcome the obstacles. And now, it has support right across the political spectrum.

Bordeaux is not resting on its laurels. The city's slogan is "The future drives us" and one of its high-tech clusters is involved in building a megajoule laser machine that will produce a temperature of up to 10 million degrees Celsius, as part of a nuclear-deterrent programme financed by the Ministry of Defence. The city is pressing for a faster TGV rail link with Paris, to reduce the time taken for this 550km trip from three hours to just two. It is also counting on Unesco's recognition of its transformation to boost tourism and investment in a region that has already given us many of the best wines in the world.

There are obvious lessons for Dublin, particularly from Bordeaux's tramway. If the two Luas lines are to be linked via College Green, an option involving no overhead power lines should be seriously considered. The same should be done in O'Connell Street, not least to facilitate the St Patrick's Day Parade.