In Wicca, Lughnasadh is 1 of the 8 sabbats or solar festivals in the Wiccan Wheel of the Year. It's the 1st of the 3 autumn harvest festivals & marks the end of summer & the beginning fall.
Originally Lughnasadh referred to the funeral games hosted by the Irish sun god, Lugh, commemorating the death of Tailtiu, his foster mother who was the last queen of the Fir Bolg. She's said to have died from exhaustion after clearing a great forest so that the land could be cultivated. Highlights of the festival included Tailltean marriages or handfastings; craft festivals in which the medieval guilds, artists & entertainers would display their talents; & the Catherine wheel.