As the sun sets and the mosquitoes multiply, a small group of young men quietly gathers at a cluster of abandoned stone farmhouses in the northern flatlands of Serbia, roughly a mile from the border with Hungary.

Tonight, led by two facilitators, the 10 plan to reach the border on foot, then cross it by climbing over several layers of fencing fortified with barbed wire. This is the next step on their long journey to flee Taliban rule in Afghanistan, with a few hoping to make it all the way to the UK.

It will require quickly scaling a ladder that will be hauled in for the purpose, avoiding detection by the many surveillance cameras that dot the border fence, and staying out of sight of police from Serbia, Hungary and Frontex – the EU’s border force.

This is the scenario unfolding daily, in secret, at multiple points in the north and west of Serbia along the border with Hungary, Croatia and Bosnia.

These countries form part of the Western Balkans route for migrants, popular with those fleeing Syria and Afghanistan, who typically travel overland via Bulgaria and Turkey, and, in some cases, Iran.