It is the day on which Zurich’s guilds ceremonially welcome spring. In the Middle Ages, church bells in the city tolled to mark the end of the working day at 6pm, which translates into Sechseläuten or ‘the six o’clock ringing of the bells’. Nowadays this tradition is associated with the burning of an effigy, the so-called Böögg. The Böögg is a symbol of winter and resembles a snowman. Setting the pyre with the Böögg alight represents driving out winter and welcoming spring.