The biggest cocaine boom in history has its origins outside towns like La Dorada, Colombia. Here, a few miles down a rutted track through the Amazon, cattle ranches and fish farms give way to endless fields of coca, the pale green shrub used for making the drug.
Apart from a few schoolteachers and occasional raids by the armed forces, the Colombian state barely exists beyond this point. To travel here, outsiders need permission from a much-feared drug cartel known as the Comandos de la Frontera, whose henchmen in military green T-shirts patrol the lanes in trucks and on motorbikes.