Other cities to choose if you're feeling asthmatic

See Naples and die - choking. That, sadly, applies to most of Southern Europe. It is the north that has embraced Green ideas most fully, particularly in terms of traffic pollution. So if you're feeling asthmatic try...

Groningen, Netherlands

This is cyclers' paradise. Half of all journeys made in the city are by bike, a higher percentage than anywhere else in Europe, and cyclists are favoured over drivers with cycle lanes, front-of-the-queue boxes at traffic lights, special cycle/train facilities to encourage commuters to bring their bikes into the city, and lots of bike-parking. Most radical of all, the city has been divided into four sectors and only bicycles and buses are allowed to pass freely between them. If a car driver wants to go from one to another, he or she has to drive out of the city and back in again.

It wasn't always like this. In the mid-1970s an ambitious programme of road-building was planned but opposition was so great, the focus turned in the opposite direction.

Zurich

Public transport is the big thing in Zurich, particularly buses, and when you hear an official say he would be "horrified if only eight out of 10 ran to timetable", it is easy to see why. Most arrive at each stop meticulously on time, the achievement of rigorously policed bus lanes and traffic light priority. Fares are not particularly cheap but there are lots of offers (family tickets etc) to make the system attractive.

Edinburgh

Arguably Britain's greenest city, in intention if not yet in fact. The local authority has set a target to reduce cars as a percentage of vehicles in the city centre from 48 per cent in 1991 to 34 per cent by 2010. Princes Street, the main shopping drag, is now only open to cars in one direction and the rest of the road has been split between extra paving for pedestrians and a bus and cycle lane. The city is also the first in Britain to promote community car share schemes. These encourage local groups - for example the residents of a street - to buy cars together and then use them co- operatively, by booking them out in advance. There are 300 similar schemes operating in other European cities and towns and they have proved most successful at discouraging unnecessary journeys - having to plan ahead encourages people to walk to the corner shop.

Edinburgh council has recently granted planning permission for the development of a "green" residential area. This will be car free, recycled materials will be used in the buildings and heating will be provided communally, using waste industrial power.