By Rob Winder BBC News Online

The danger of crossing live rails in the dark is all part of the appeal of to graffiti artist Craig.

Graffiti has attracted the wrath of Keep Britain Tidy

The adrenaline rush of finding a suitably clean train or wall to provide a blank canvas for his designs is one he shares with like-minded individuals across the country.

They see their often complex and accomplished designs as quite distinct to the names clumsily scrawled on any surface by less talented individuals.

But there are many more people who don't share their enthusiasm for a practice which costs Britons millions of pounds a year to clean up.

The Keep Britain Tidy campaign says graffiti artists are holding the UK to ransom, while police are attempting to serve Anti Social Behaviour Orders (Asbos) on persistent offenders.

Is there any chance that the threat of heavy fines or a spell in jail will persuade the artists to change their ways?

'Incriminating evidence'

"We plan our route into the train yard and then wait for an opportunity", says Craig, from East Anglia.

"You have to cut holes in fences, climb over walls, do the piece and take photo's - all while making sure you don't leave any incriminating evidence behind.

"We always walk down the track in the opposite direction to the trains - that way you're less likely to get hit by one from behind.

"You also need a story sorted as to why you're down a dark road in the middle of the night"

Creative outlet

With the possibility of being electrocuted or hit by a passing train added to the very real possibility of arrest, it can be difficult to see the appeal of life as a graffiti artist.

But those involved see the risks as part of the appeal of a practice which sprang up in late 1970's New York ghettos.

Some graffiti writers consider themselves 'serious' artists.

It was an integral part of hip-hop culture, alongside rapping, dj-ing and break dancing.

As that culture spread to Europe and beyond, some young people found a creative outlet that they believed reflected the harsh nature of urban life.

A few exponents, like Bristol-based Banksy, have broken into the mainstream and have their work featured in exhibitions.

Craig says his work appears on clothing and album covers.

Studies of graffiti artists have cited it as one way in which young men define their identities.

Others believe it is a way of marking territory - the art itself is often secondary.

Recognition

"Most do it for the simple buzz of breaking into a yard in the early hours and getting away with it", says former artist Gat.

"But serious artists also do trains as it makes you seem like a 'hardcore' writer and gets you recognition."

Many are well aware of why it is that other people often fail to share their enthusiasm.

"It is vandalism," admits Brighton-based Tiny, "but compared to a lot of things that go on in the world it's not that bad."

Admiration

The police don't see it that way. They are using Asbo's to target repeat offenders, sometimes before they even reach a train yard.

"Graffiti frightens the general public," says Chief Inspector Dave Dickason of the British Transport Police, "and it costs London Underground and the train companies thousands of pounds."

British police have set up their own database of artists work in an attempt to keep tabs on artists as far away as San Francisco and Germany.

Typical Graffiti ASBO Banned from entering train depots and sidings Banned from carrying spray paint and marker pens Banned from aiding and abetting other artists.

Despite this, Mr Dickason admits a grudging respect for some artists' abilities.

"People like Banksy have got real talent - they just need use it in a more constructive way," he says.

But graffiti artists maintain they will keep spraying, despite the threat of ASBO's.

"They might make life more difficult for writers," says Tiny, "but illegal pieces are too much of a buzz for people to stop doing them."