Running, traffic-free, along old railway lines, canal towpaths, forest tracks, riversides and urban spaces the routes will eventually link almost every major town in Britain, passing within two miles of half the population.

Cycle Network

Only 2% of UK journeys are made by bike In cycle-friendly Germany, 10% are The network will be 10,000 miles by 2005 It will pass within two miles of 30m people It will carry 100m journeys a year About 60% will be utility trips and 40% leisure

Its creators say their mission is to popularise the bicycle, and are targeting the 75% of commuters who they say live within five miles of work and could do their bit to relieve congestion and pollution.

The plus sides sound good - a healthier workforce, quieter, cleaner roads and perhaps a warming sense of self-satisfaction at taking some direct action to improve the environment.

But the more pragmatic among the cycling community are sceptical.

"I'd like to think it will make a difference, but I doubt it very much," said Gideon Mason, who runs Dirt and Dreams bike shop in London's trendy Notting Hill - which he admits has its fair share of "fair-weather" cyclists.

"We English people are very lazy. If its a choice between a 30-minute cycle ride with a little hill or the luxury of a car journey, most people will take the car every time."

Cycle routes will criss-cross Britain

His comments are supported by statistics which suggest that those in Holland or Germany are five times more likely to cycle to work than those in the UK where just 2% use pedal power.

The temperemental British weather - where a sunny start is no guarantee of a dry journey - provides no encouragement to anyone considering trading in their petrol-guzzler for a two-wheeler.

Although part of the National Cycle Network follows existing, traffic calmed, roads, anyone commuting on a bicycle will have to take their life into their own hands on busy, traffic-filled highways.

Cyclists are 10 times more likely to be killed on the roads than motorists. Those who are inexperienced or frail face an even more perilous journey.

Security is a big concern

But traffic is not the only danger. Bicycle crime is one of the biggest headaches for the cyclist.

Lock your cycle to a city centre lamppost and it is only a matter of time before a boot buckles its wheels, or a thief spares you the trouble of having to cycle home.

"At least a third of our customers will get their bikes stolen within six months," is the startling revelation from Mr Mason.

"The problem could be solved if the councils would pay for secure lock-ups all over London, but that is just not going to happen."

Campaigners say there have been some successes, however.

Famed for his 'Two Jags', John Prescott tries pedal power

Sustrans (Sustainable Transport) - the group behind NCN - has had success with workforce partnership trials, where employers work with the charity to encourage employees to commute by bicycle.

Initially a trial was set up with businesses in South Wales within 1km of the NCN. The initiative has now been extended to NHS Trust hospitals, the National Assembly for Wales and Sainsbury's.

By 2005 Sustrans wants to partner and link to the network 100 large corporations, 50 NHS Trust hospitals, 50 universities and 200 local councils.

John Grimshaw, director and chief engineer of Sustrans, said: "What we're trying to do is persuade people who don't cycle to start.

There's no way a national cycle network is of any use to someone wanting to ride a bike to go shopping, to school, to work or to train

Shelagh Hargraves Cyclist

"The bicycle is a wonderful piece of technology which is very suitable for today. It's environmentally friendly, it's cheap, it's quick and it's very good for many short journeys."

The government set itself a target of doubling cyclist numbers between 1996 and 2002. That target now looks almost impossible to meet.

Cyclists themselves say the government should spend more money on making existing roads more accommodating for bicycles.

Stuart Reid, of the Cyclists Touring Club, said: "We want to see space given back to bikes. We want to see traffic in many instances slowed down. We want to see consideration on the roads.

"There are many things which can be done to make cycling on the road in the city as pleasant an experience as cycling off down a leafy lane."

Shelagh Hargraves, of the Welsh Cycling Association, said: "There's no way a national cycle network is of any use to someone wanting to ride a bike to go shopping, to school, to work or to train.

"The support given to the network is, in my view, dangerous in that the non-cyclist perceives that 'cyclists should be on cycle tracks, not holding me up on my way to work'."