The directions from Stockport Tourist Information were enthusiastic. 'Turn left on to the A6, and walk across the open land. You can't miss it,' said the telephonist.

Stockport, which has until now been famous only for its hat museum, has never seen anything like it. Over the last two months hundreds, if not thousands, of people have been making determined pilgrimages there from London, Edinburgh, Carlisle and Milton Keynes. They come by train and car in pursuit of news spreading by word of mouth and internet: Stockport is home to Britain's first-ever Amsterdam-style coffee shop.

Tucked away in a quiet, cobbled retail centre, the innocuous-seeming 'Dutch Experience' is betrayed only by the sound of garrulous chatter and the distinctive smell of marijuana wafting in the autumn air. Outside, between the pictures of cannabis leaves, signs warn: 'Over 18 only, ID required' and 'No alcohol, or drunk and disorderly persons on the premises'. Inside, alcohol is the last thing on people's minds.

From its opening at 10 in the morning to closing at 10 at night, the Dutch Experience is packed with people rolling joints, inhaling deeply and grinning peacefully. By lunchtime last Wednesday, there were at least 50 people in its two rooms, by evening over 100. No one bothered to hide this still illegal activity. It's all totally open.

Its founder, Colin Davies, a former carpenter, said the numbers increased sharply after the Home Secretary, David Blunkett, announced that cannabis possession will no longer be an arrestable offence, and reckons he gets more than 500 visitors a day. 'I've created a monster,' he laughs, as he sits on the bench, taking a puff. 'They're coming from all over the country - the closest coffee shop is in Holland.'

His customers sit playing cards or table football, drinking coffee or Coca-Cola, chatting and criticising each other's joint-rolling abilities. 'I've never seen anyone take so long to roll a spliff,' scolds one woman.

Some are nervous on their first visit, while others have been coming every day since it opened on 15 September. Paul Cooper, 18, who this week starts working for a government project on drug use, is one of the regulars: 'It's such a calm, quiet atmosphere in here; there's never been a raised voice. There's been no fights. It's not like a pub, where you drink 10 pints of Stella, and it all gets very rowdy.'

Billy Roberts, 44, a bricklayer, comes as often as he can from Bolton. 'This place is brilliant - it's just like the ones in Holland. You know what you are getting when you come here. Colin Davies is making history - he's a real hero,' he puffed.

Davies became a cannabis activist after shattering his back in a fall and finding that the illegal drug was the best one for relieving pain. In 1996 he started the underground medical marijuana co-operative, secretly growing cannabis as a painkiller for people suffering from multiple sclerosis and rheumatoid arthritis, who had to provide a doctor's certificate to prove eligibility. He was prosecuted twice by police, but both times juries simply acquitted him because he was helping sick people.

But it was the Conservative politician Peter Lilley who inadvertently persuaded him to open the Dutch Experience. On a plane to visit a coffee-shop owner in Amsterdam, Davies read about Lilley calling for the legalisation of cannabis, and by the time he landed he thought the time was right for coffee shops in Britain.

The purpose of the coffee shop is to use the money made from social users of cannabis to provide it free - or at cost price - for medicinal users. 'People in wheelchairs shouldn't have to pay for their medicine - they should get it free, and that's what we're doing,' said Davies.

One woman, in her early forties, whose hands are crippled with rheumatoid arthritis, was particularly appreciative: 'This stuff is much better quality than what you get on the street - I've been sold Oxo cubes so many times. It gets to my bones better - the pain relief is far better than anything I can get from the doctor. And I get it for free - I couldn't afford to buy it.'

Two weeks before opening, Davies and his Dutch partner Nol van Scheik wrote to the police and the council setting out their plans. The police raided on the day he opened, but they reopened a few hours later and since then the police have left them alone. The council didn't reply to the letter, but instead sent them a rates bill. 'That's the only licence I will get from the council,' said Davies.

He stays on the right side of police tolerance by not selling cannabis openly through a booth with a menu - he only plans to do that when he feels the time is right. But he makes sure customers have no trouble getting hold of either super-skunk grass or Lebanese gold resin.

The council has not had a single complaint from the public, and is turning a blind eye. Its leader, Fred Ridley, said: 'This is not a matter for the council, but for the police. If someone wants to test the law - and that's the way the law has been changed before - they must accept the consequences if the law of the land is enforced.'

Manchester Police said in a statement: 'We recognise there is ongoing debate and research into the medical benefits or otherwise of cannabis. The police, in appropriate cases, exercise discretion and judgment.'

The Dutch Experience has had open support from the local MEP, Chris Davies, who has visited twice. 'I applaud it. It seems an excellent way of meetings people's desire to try things other than alcohol without leading them on to harder things,' he said.

Other cannabis campaigners are eyeing the Stockport trailblazer with envy, and there are already plans to open them in Worthing, Taunton and Brixton.

anthony.browne@observer.co.uk