At the call "Morgestraich, vorwärts marsch!" (Morgestraich, forward march!) the drum rolls begin and the musicians start their processions through the cobbled streets of Basel's old town.
Spectators line the parade routes for as long as they can bear the cold and then head into local restaurants to sample Fasnacht specialities such as Mehlsuppe (flour soup), Zwiebelkuchen (onion quiche) and Käsewähe (cheese flan).
The following 72 hours are a riot of colour and music as singers deliver satirical verses, costumed Fasnacht participants throw sweets to passers-by and brass bands march around the streets.
"Basel is normally a serious city," Dominik Wunderlin, curator at Basel's Museum of Cultures told the swissinfo website ahead of this year's Fasnacht.
"It's a city of commerce and trade and people don't always have lots to smile about.
"On these three days you can certainly let off steam, although visitors from outside who know other Fasnachts are usually astounded how deadly serious Fasnacht is here."