Reek Sunday, also known as Garland Sunday, is observed in Ireland on the last Sunday of July. This annual pilgrimage takes place at Croagh Patrick, a mountain in County Mayo that is associated with Saint Patrick. The mountain, originally known as Cruachán Aigle, has historical significance as a site of pagan pilgrimage before Christianity. According to legend, Saint Patrick fasted on its summit for forty days during Lent, which has led to thousands of pilgrims climbing the mountain each year to honor him. Approximately 100,000 pilgrims ascend Croagh Patrick annually, with between 15,000 and 30,000 participating specifically on Reek Sunday. The event is traditionally led by the Archbishop of Tuam and takes about two hours to climb, with local rescue teams on alert due to the increased risk of injuries.