The terracotta muddle of Dubrovnik old town dazzled below, but I was 1,300ft up in the wild. Balkan whip snakes slithered through rosemary thickets nearby, and carob pods longer than Curly Wurlys slapped me in the face – but I was focused on looking for blue moons. These bright little icons have been spraypainted on everything from beehives to an abandoned Yugo as they – literally – trailblaze the Camino Dubrovnik, Europe’s newest pilgrimage trail.