The Marian Apparitions at Lourdes were reported in 1858 by Bernadette Soubirous, the 14-year-old daughter of a miller from the town of Lourdes in southern France.

From 11 February to 16 July 1858, she reported 18 apparitions of "a Lady". Soubirous described the lady as wearing a white veil and a blue girdle; she had a golden rose on each foot and held a rosary of pearls. After initial skepticism from the Clergy, these claims were eventually declared to be worthy of belief after a canonical investigation, and the apparition is known as Our Lady of Lourdes.

According to Soubirous, her visions occurred at the grotto of Massabielle, just outside Lourdes. On 16 July 1858, Soubirous visited the grotto for the last time and said: "I have never seen her so beautiful before." On 18 January 1862, the local bishop declared: "The Virgin Mary did appear indeed to Bernadette Soubirous." In 1958, Pope Pius XII issued the encyclical Le plerinage de Lourdes ("The pilgrimage to Lourdes") on the 100th anniversary of the apparitions. Pope John Paul II visited Lourdes three times; Pope Benedict XVI visited Lourdes on 15 September 2008 to commemorate the 150th anniversary of the apparitions.

Soubirous was canonized a saint in 1933 by Pope Pius XI.

Bernadette Soubirous (; French: [bɛʁnadɛt subiʁu]; Occitan: Bernadeta Sobirós [beɾnaˈðetɔ suβiˈɾus]; 7 January 1844 – 16 April 1879), also known as Saint Bernadette of Lourdes, was the firstborn daughter of a miller from Lourdes (Lorda in Occitan), in the department of Hautes-Pyrénées in France, and is best known for experiencing Marian apparitions of a "young lady" who asked for a chapel to be built at the nearby cave-grotto at Massabielle. These apparitions occurred between 11 February and 16 July 1858, and the woman who appeared to her identified herself as the "Immaculate Conception."

After a canonical investigation, Soubirous's reports were eventually declared "worthy of belief" on 18 February 1862, and the Marian apparition became known as Our Lady of Lourdes. Since her death, Soubirous's body has remained internally incorrupt.

The Marian shrine at Lourdes (Midi-Pyrénées, from 2016 part of Occitanie) went on to become a major pilgrimage site, attracting over five million pilgrims of all denominations each year.

On 8 December 1933, Pope Pius XI, declared Soubirous a saint of the Catholic Church. Her feast day, initially specified as 18 February – the day Mary promised to make her happy, not in this life, but in the other – is now observed in most places on the date of her death, 16 April.