Every year on the night of January 16, the eve of Saint Anthony's day, the patron saint of animals, the paved streets of San Bartolome de Pinares, Spain, of 600 people are transformed into a sort of racetrack in which the fences are burning logs.
"It's a festival in which the horses are sanctified by the flames, they are liberated from all their ills," said Quique, 30, who takes part in the festival every year.
Tree branches for the fires are collected for weeks ahead of the festival. The flames are regularly doused with water to produce columns of smoke intended to purify the animals. The tradition is under threat from animal rights groups, who say the horses suffer as they leap over the flames.