Thousands of revellers have attended the opening of the carnival season in predominantly Catholic regions of the country.
An estimated 12,000 people in colourful costumes filled the streets of Lucerne city in the early hours of the morning to witness the Big Blast – the traditional signal for the six-day festival.
Major carnivals, including pageants and cacophonous music, are also underway in St Gallen, Solothurn and the Italian-speaking city of Bellinzona.
In mainly Protestant regions, including the capital Bern, the annual event will be launched next week.
Revellers in Basel will have to wait until the beginning of March for what they call "the most beautiful days of the year".