The Grotto of Our Lady of Lourdes is a one-seventh-sized replica of the famed shrine in Lourdes, France, where the Virgin Mary appeared to Saint Bernadette on 18 occasions in 1858. Visiting that site on one of his 50 trips abroad, Father Sorin vowed to reproduce it on the Notre Dame campus, and a gift from Rev. Thomas Carroll, a former theology student, made it possible in 1896. Boulders weighing as much as two tons or more from surrounding farms were used in its construction. Hundreds of thousands have visited the shrine to pray and/or light candles over the years.