During the January carnival period, villagers shod in heavy boots, shaggy costumes and rather "unconventional" hats march through the countryside of Kastav and coastal Rijeka in Northern Croatia: the bell ringers (Zvončari in Croatian). They are an awesome lot to behold, and they make a lot of noise! Imagine heavy brass bells for "tails" or around your waist, jumping around and shouting at full volume - well, you can imagine that this would wake you up - or, as the case may be, chase away the ghosts of winter.

This tradition is considered an intangible cultural heritage by UNESCO. The custom dates to Slavic pagan days and remains a cherished tradition in this region. The primary task of bell ringers is to scare away the evil winter spirits and to invite in a new spring.

Bell ringer groups usually consist of 10 to 20 members, but can be much larger on weekends and festive days. The costumes vary from region to region. In the Rijeka area, the standard costume includes white trousers, a striped shirt, and a sheepskin throw. Bell ringers from the western Kastav region wear hats covered with paper flowers instead of animal masks. Yet others are covered in a floor length covering of colourful paper ribbons. Only the Halubian bellringers wear large "wild thing" masks instead of hats. This was previously the most common form of head covering for bellringer groups, but during the Italian occupation they were prohibited. Regardless of the costume variant, all of them carry brass bells, but they may ring them differently.

Their route through the villages of their area can sometimes be up to twenty kilometres long. Some of these groups move around in a procession from village to village in a swaggering motion and bump each others hips while moving, a very strenuous way of moving forward, requiring some level of skill and strength. Others run fast from house to house jumping and making their costumes jiggle. Costumes vary widely from village to village, with extraordinary headgear and shaggy fur, or flowing paper ribbons. What they usually have in common is either one large bell or belts of bells around their waist.

As a highlight of their visit to each village, ringers arrive in the centre, where they begin forming a circle and bounce around, ringing fiercely. After that they are usually approached by the residents of the village and offered some refreshments, before moving on to the next village.

The processions culminate on Shrove Monday and Tuesday, marking the end of carnival season and the beginning of Lent. On the last day of the carnival period a puppet called Pust is "put on trial" for all misdeeds on the past year. The unfortunate puppet is then sentenced to death by fire or hanging. Music and dance often accompanies the festivities.

The wearing of masks, with which humans celebrate fertility rites, drive away evil spirits and mark the passage of winter into spring is a fixture of many civilizations and can be found in all parts of the world. The social significance is the relationship and cohesion of villages in which the ritual takes place, showing mutual support for each other. The custom also involves the preparation of special meals, and the maintenance of ancient handcrafts, such as making mask and bells. Elements of folk theatre and differences in ethnicity are reflected in the varying costumes.