The International Hot-Air Balloon Festival in Château-d'Oex is a hot-air balloons festival that has taken place every year during nine days at the end of January in Château-d'Œx, Switzerland since 1979. It is attended by nearly a hundred balloons from over twenty countries. It is famous for taking place in a snowy valley (most of the time) and also for a unique event : the "night-glow" show, where all the balloons are exposed on the mountain, lit by their burners, during the evening of the 7th day.