Lughnasadh (pronounced [ˈlu.nə.sə]) is the celebration of the beginning of the harvest in Gaelic paganism and Wicca. It occurs on 1 August (2 August in Wicca), approximately halfway between the summer solstice and autumnal equinox. It is one of four seasonal celebrations in Gaelic pagan tradition (along with Samhain, Imbolc, and Beltane), and one of the eight major Wiccan festivals on the Wheel of the Year.
In later history, it has given rise to secular festivals celebrated in Ireland, Scotland, and the Isle of Man, some of which include Christianised forms of the ancient pagan practice of making pilgrimages to hills and mountains. On Reek Sunday, a Christianised festival based on Lughnasadh, people make pilgrimages to the top of Croagh Patrick in Ireland.
Today, reconstructions of the festival are celebrated by Celtic neopagans and Wiccans as a religious holiday. It is also a cultural holiday to some people in the Gaelic lands.
According to Gaelic mythology, Lughnasadh was started by the god Lugh in honour of the death of his mother, Tailtiu, who died clearing Ireland for agricultural purposes.