Motoring: No car park at a grand prix? Melbourne did without it.

Motor racing improves road-cars, or so the car companies will tell you. Sure. And cigarette smoking makes you hunky, wear Calvin Kleins and you'll look like Kate Moss, and Michael Schumacher wears an Omega so they must be great watches. In fact, car companies go motor racing for the same reason that they hire Nicole, Nigel Havers and swanky advertising agencies: to flog cars. As proof, those car makers who produce formula one racing engines (Renault, Peugeot, Mercedes, Ford) generally make the least refined road-car engines. Yamaha, on the other hand, can't seem to make an F1 engine capable of powering Damon Hill around a single lap. Yet its motorbike engines are fabulous. Go figure it.

Yet, unusually, the recent Australian GP in Melbourne did come up with a solution to arguably the greatest of all problems facing the motor car. It was nothing to do with carbon fibre brakes or advanced aerodynamics; on fact, it had nothing to do with the action on the track at all. It was the way they solved the thorny problem of traffic congestion.

Normally, at a GP meeting, you take more time trying to get into and out of a circuit than you do watching the action. It's like a microcosm of peak-hour traffic in any big British city, but worse.

The Melbourne organisers decided not to have any car parking at all near the circuit. The roads around the Albert Park track, only a mile or so from the city centre, were blissfully uncongested. Instead, if you wanted to go to the races - and 290,000 people did, over the three-day meeting - you had to go by train, tram (Melbourne has a good streetcar network), bus, taxi or chauffeur-driven limo.

Visitors got into and out of the circuit quickly and easily. The various forms of public transport were organised to complement each other. Trains ferried people from around the city (and the country) to meeting-points nearer the circuit, from where trams and buses whisked them to the track. Melbourne pioneered such a system for its GP last year, and it worked a treat.

This year, unfortunately, it wasn't quite so good. In a nasty piece of old-fashioned union opportunism the tram and train drivers decided to call a quick strike on the Saturday and Sunday. Instead, extra buses (which in Melbourne are privatised) were drafted in, to fill the void. As a boon, they were free - the organisers picked up the tab. They did a spectacularly good job, even if the eventual attendance for the meeting was 110,000 shy of last year's total.

In Britain, a "no car park" policy would be unthinkable at a major sporting event. Yet Melbourne showed it can work, as long as the public transport alternative is good enough. (And, to be fair, most British cities have public transport at least as good as Melbourne's.)

Equally, such a policy would be unthinkable in British cities, although some councils are encouraging fewer car parking spots at new office buildings. We rabbit on about ways to reduce traffic congestion in our great conurbations - and then we let NCP and the like build more and more car parks. No car parks mean fewer cars, just as assuredly as no junk food means fewer fatties.

In the bit of central London where I work, there are at least six major car parks within a one-mile radius of my office, and many smaller ones. They attract commuters like magnets. New ones open regularly.

Of course, cars are sometimes the best way of getting about. But not when commuting into cities at peak hours from the suburbs, or - perhaps more surprisingly - when getting to and from a grand prix.