A bonfire is a large but controlled outdoor fire, used either for informal disposal of burnable waste material or as part of a celebration.
In many regions of continental Europe, bonfires are made traditionally on 16 January, the solemnity of John the Baptist, as well as on Saturday night before Easter. Bonfires are also a feature of Walpurgis Night in central and northern Europe, and the celebrations on the eve of St. John's Day in Spain. In Finland bonfires are tradition on Midsummer Eve and Easter, also in midst of May celebrations.
Bonfire traditions of early spring, lit on the Sunday following Ash Wednesday (Funkensonntag), are widespread throughout the Alemannic German speaking regions of Europe and in parts of France. The burning of "winter in effigy" at the Sechseläuten in Zürich (introduced in 1902) is inspired by this Alemannic tradition. In Austria "Osterfeuer", Easter fires, are widespread, but also regulated in some cities, districts and countries to hold down the resulting annual peak of PM10-dust immission. There are also "Sonnwendfeuer" (solstice fires) ignited on the evening of 21 June.
Since 1988 "Feuer in den Alpen" (fires in the Alps) have been lit on a day in August on mountains so they can be seen from afar as an appeal for sustainable development of mountain regions.
In the Czech Republic, the festival called "Burning the Witches" (also Philp & Jacob Night, Walpurgis Night or Beltane) takes place on the night between 30 April and 1 May. This is a very old and still observed folk custom and special holiday. On that night, people gather together, light bonfires, and celebrate the coming of spring. In many places people erect maypoles.
The night between 30 April and 1 May was considered magical. The festival was probably originally celebrated when the moon was full closest to the day exactly between the spring equinox and summer solstice. People believed that on this night witches fly on the Sabbath, and indeed this is one of the biggest pagan holidays. People also believed, for example, in the opening of various caves and underground caverns in which treasures are hidden. The main purpose of this old folk custom was probably a celebration of fertility.