The Boeoegg, a snowman made of wadding and filled with firecrackers, burns atop a bonfire in the Sechselaeuten square in Zurich April 13, 2015. As the bells of St. Peter's church chime six o'clock, the bonfire below the "Boeoegg" is set alight and mounted guildsmen gallop around the pyre to the tune of the Sechselaeuten March. The faster the head of the "Boeoegg", the symbol of winter, catches fire and explodes, the warmer and more beautiful the summer will be. REUTERS/Arnd Wiegmann TPX IMAGES OF THE DAY