Selson Lopez is a charming, rather likeable man, who used to grow marijuana and coca for a living, and also robbed ancient Indian tombs for their highly prized gold artefacts. Today he is an upstanding student of that most respectable of trades, eco-tourism.

For years, Selson’s neighbour, Luis Riatiga, undertook the long chemical processes in which coca leaves are transformed into cocaine. Yet when we meet, he is roasting organic coffee, which he and his neighbours now produce, along with cocoa and honey.

And where Richard Velasquez once ran over a flimsy bridge by dead of night, sacks of coca leaves destined for illegal trade on his back, today he is a community leader and activist – a man who travels around Colombia to explain to other communities how a grassroots movement can, with determination, imagination and some government help, turn its back on lawlessness and embrace a more positive, peaceful future.

All of these men and their families now have a stake in the Posada Turística San Rafael, an eco-tourist lodge close to Tayrona National Park on the Caribbean coast near Santa Marta. The stories they tell are of the lawlessness and violence that was Colombia for many years. But while the country still faces huge challenges, maybe the big story there today is how much has changed for the good.

Despite continuing struggles with paramilitaries such as Farc, the Marxist guerrillas who held the French-Colombian politician Ingrid Betancourt and others for years, and who still operate deep in the jungle; despite recent scandals concerning brutality and corruption by the army in this, Colombia’s particular war on terror; despite continuing poverty in cities such as Medellín and Bogotá as well as in the countryside; and despite the continued existence of an industry that supplies the globe with cocaine, parts of Colombia have been utterly transformed – and most foreigners’ perceptions of the country are probably a good ten years out of date.

Medellín, long a byword for narco-crime and violence, is now held up as a model of urban regeneration – the city of choice for many multinationals opening a company HQ in Colombia. Crime clans such as the Escobars are disappearing. Most of the paramilitaries have largely been pushed to the fringes of this vast country.

Meanwhile, in some parts of the countryside, a grassroots movement, supported by the central government, is seeing coca plantations uprooted as communities turn instead to more benign businesses such as eco-tourism and growing organic crops, including cocoa, honey and, of course, Colombia’s other most famous export, coffee.

It’s worth noting that the Colombian cocaine industry is pretty well entirely geared towards export. The indigenous people might chew coca, which can sustain them on long journeys at high altitudes, or through arduous days in the fields. But relatively few Colombians touch cocaine, a drug that has become socially acceptable in some circles in the UK, dished up like an extra pudding at middle-class dinner parties from Notting Hill to Didsbury. That people who would be loathe to eat chicken that wasn’t free-range or bananas that weren’t fair trade might cheerfully snort a line of “charlie” would be an irony lost on most Colombians.

The coffee-growers at San Rafael are also surprised when I explain how competitive British supermarkets are over their ethical credentials. Come to think of it, what a great TV commercial for Waitrose or Marks & Spencer could be made using these photogenic people and their amazing stories. A note on their products telling their stories would certainly shift units, not least to shamefaced Brits who can’t resist a line or two of cocaine, but who worry about bad things happening to good people further down the supply chain.

That might be a year or two away, but for this little bit of Colombia, change began in 2003, when some 885 locals joined together to launch Familias Guardabosques, or Guardians of the Forest, and then struck a deal with the government, brokered by “Vicky”, as they affectionately call Victoria Eugenia Uribe, sister of Colombia’s president and director of the Presidential Programme Against Illicit Crops. Under the deal, which was later rolled out to include more farmers, each family would receive 600,000 pesos (about £170) every two months in return for uprooting all the coca plants in the area.

Like many Colombians, Richard Velasquez, a persuasive advocate for Guardians of the Forest, is proud of how the country is changing, and gets almost misty-eyed when he talks about “el Presidente de la República, Señor Alvaro Uribe”. Uribe has his critics, not least neighbouring Venezuela’s populist president, Hugo Chávez, who describes him as an American stooge.

But Velasquez likens him to those extraordinary national leaders, like Nelson Mandela or Winston Churchill, who appear in their country’s hour of need and make a real difference. “It was absolutely vital we made this change,” explains Velasquez, who travels to conferences throughout Colombia to export this model for a better future.

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