He set off on the first leg of his epic journey with a fanfare of publicity, not to mention an appropriately alternative farewell pre-dawn party on Bristol docks featuring drummers and someone playing a conch shell.

Mark Boyle's idea was to walk to Mahatma Gandhi's birthplace without a penny in his pocket, relying on the kindness of strangers for food and shelter to prove that a better world without money really was possible.

Boyle got as far as Calais before he realised that, unable to speak French to explain his mission and unable, frankly, to get much vegan food in this part of northern Europe, he faced starvation.

He was forced to turn round, recross the Channel and yesterday was to be found in genteel Eastbourne, East Sussex, explaining why a two-and-half-year pilgrimage had turned into a month-long jaunt to France and back.

"The problem was that I just couldn't explain to people in France what I was doing," Boyle told the Guardian. "People seemed to think I was a refugee looking for work. The idea was to ask people if I could help them and in exchange receive food and a place to stay. But they thought I was begging."

Boyle did study French at school in Ireland for six years but as soon as he stepped off the ferry he found he could remember hardly a word. His clothes did not help. His walking outfit includes vivid yellow trousers, open-toed sandals that expose his blackened toenails and a T-shirt bearing the slogan Community Pilgrim.

"I call the clothes my ice-breaker," explained Boyle. "In Britain people respond to the outfit well. It's a way in. In France clearly they are a bit more sophisticated and they weren't impressed."

By the time Boyle reached Calais he had already picked up two companions who were intending to go with him to India, including 17-year-old Katie. As soon as they realised they were not particularly welcome in France they changed their plans and started to head for Belgium. But by then they had only half a chocolate bar, a bag of nuts and raisins and three tins of soup between the three of them. "We weren't going to get there. We had to turn back," said Boyle.

Fortunately Katie's mother had insisted that she carry travellers' cheques in case an emergency arose. The cheques were cashed and the white cliffs of Dover came back into sight again much more quickly than Boyle had hoped.

The pilgrimage had been forming in Boyle's imagination since he saw the film Gandhi while studying business and economics at university.

A few years later Boyle was in Bristol, where he worked as a manager for an organic food store, putting the world to rights with friends when it hit him that money was at the root of everything that was going wrong.

He set up the Freeconomy website (justfortheloveofit.org). The idea is that like-minded people sign up, list their skills and donate them to others. In return they receive favours back. For instance, a hairdresser may give a mechanic a haircut and in exchange the mechanic would fix the hairdresser's bicycle. No money ever changes hands.

"I have a vision of a money-free economy in which everyone cares for each other," said Boyle, speaking yesterday from a school in Eastbourne, which has given him a place to stay in return for work he is doing on the school's organic garden.

The website appears to have been successful. Boyle says 4,200 people with 900 different skills from 85 countries have signed up.

He insists that his is not a hippyish vision - he hates being labelled a hippy - but a practical response to the growing world problems of global warming and the increasing cost of oil.

He believes that within 10 years the world will face such a huge crisis because of these twin problems that people will be forced to look inward and depend on their own communities to survive.

So the pilgrimage was partly an attempt to draw attention to Freeconomy and partly to try to prove that there is a caring world out there.

He packed a change of clothes, unfurled a flag bearing the motto "12,000km for peace", daubed "peace" on his rucksack in languages including Arabic, Russian, Hindi and Chinese and headed for Porbanda in Gujarat on January 30, the 60th anniversary of Gandhi's death. He didn't plan, believing it was best to let fate take its course.

Boyle, 28, said it went brilliantly as he walked from Bristol to Dover. People smiled, people helped. He walked up to 47 miles a day. His "boys", as he calls his feet, suffered but his stomach was full. It was all going so well until he arrived on foreign soil.

Still, Boyle is nothing if not an optimist. He has apologised to his supporters for using money to get home but is not going to give up, just rejig his plans. He now plans to spend the next year travelling around Britain asking people if he can help them, in the meantime getting language lessons from members of the Freeconomy network.

Then he will head back to the continent - he may bypass France - and try again. He believes that Europe will always be the hardest place to crack. Once he gets to Turkey he is sure people will be more open and welcoming.

"I know people are laughing at me," he said. "I don't mind. I'm going to go and do it all again. But for now if all I've done is give people something to smile about then that's not so bad. There are worse things going on in the world."

What to say en route

French

Je n'ai pas d'argent et j'ai faim. Puis-je vous demander de m'aider?

(I've got no money and I'm hungry. Can you help me please?)

Welsh

Ble alla' i gael pryd am ddim?

(Do you know where I can get a free meal?)

Gaelic

Tha feum agam air àite-fuirich

(I need a place to stay)

(Common) Cornish

A yllta ri dhymm gorrans, mar pleg?

(Can you give me a lift, please?)

Sources: BBC, Welsh Language Board, Cornish Language Partnership and Research Department

· This article was amended on Tuesday March 4 2008. In the article above (about a campaigner hoping to walk penniless from Bristol to Mahatma Gandhi's birthplace in India) we said he set off on the 60th anniversary of Gandhi's birth. January 30 was the anniversary of Gandhi's death. We included Hindu in a list of languages, when we should have said Hindi. These errors have been corrected.