The beautiful valley of Chistau, in the Sobrarbe, resorts during the night of January 16 to 17 to a particular method to scare away evil spirits: noise. After a copious dinner in community, a caravan of neighbors walks through the villages of the valley sounding the trucos or cowbells, organizing a great roar to which some people also contribute by sounding horns of animals like those used in grazing.
The procession is not limited to interpreting the serenade in the streets of the villages, but during the trip in cars on the roads of the valley stops to play the cowbells inside the tunnels.
This particular way of invoking protection for the animals of the valley, recovered some two decades ago, is known as the Fiesta de los Trucos and is anxiously awaited by all. It is celebrated every San Antón’s eve, no matter how adverse the weather conditions are (which generally are, and a lot, on those dates). It is worth mentioning the enormous and beautiful cowbells that some people have developed expressly for the occasion, like this one shown in the attached picture.