Lourdes is a town in southwestern France, in the foothills of the Pyrenees mountains. It’s known worldwide for the Sanctuaires Notre-Dame de Lourdes, or the Domain, a major Catholic pilgrimage site. Every year, millions visit the Grotto of Massabielle where, in 1858, the Virgin Mary is said to have appeared to a local woman. Pilgrims can drink or bathe in water flowing from a spring in the grotto.