11 February 1858, Soubirous went with her sister Toinette and neighbor Jeanne Abadie to collect some firewood and bones in order to buy some bread. After taking off her shoes and stockings to wade through the water near the Grotto of Massabielle, she said she heard the sound of two gusts of wind (coups de vent) but the trees and bushes nearby did not move. A wild rose in a natural niche in the grotto, however, did move.
Referenced from various sites/books including Wikipedia.
“…I came back towards the grotto and started taking off my stockings. I had hardly taken off the first stocking when I heard a sound like a gust of wind. Then I turned my head towards the meadow. I saw the trees quite still: I went on taking off my stockings. I heard the same sound again. As I raised my head to look at the grotto, I saw a lady dressed in white, wearing a white dress, a blue girdle and a yellow rose on each foot, the same color as the chain of her rosary; the beads of the rosary were white....From the niche, or rather the dark alcove behind it, came a dazzling light…'
Soubirous tried to make the sign of the Cross but she could not, because her hands were trembling. The lady smiled, and invited Soubirous to pray the rosary with her. Soubirous tried to keep this a secret, but Toinette told her mother. After parental cross-examination, she and her sister received corporal punishment for their story.
Three days later, 14 February, Soubirous returned to the Grotto. She had brought holy water as a test that the apparition was not of evil origin/provenance: "The second time was the following Sunday. ... Then I started to throw holy water in her direction, and at the same time I said that if she came from God she was to stay, but if not, she must go. She started to smile, and bowed ... This was the second time."
Soubirous's companions are said to have become afraid when they saw her in ecstasy. She remained ecstatic even as they returned to the village. On 18 February, she spoke of being told by the Lady to return to the Grotto over a period of two weeks. She quoted the apparition: "The Lady only spoke to me the third time. ... She told me also that she did not promise to make me happy in this world, but in the next."
Soubirous was ordered by her parents to never go there again. She went anyway, and on 24 February, Soubirous related that the apparition asked for prayer and penitence for the conversion of sinners.
Soubirous witnessing the apparition of the Virgin Mary. Stained glass, Bonneval.
The next day, she said the apparition asked her to dig in the ground and drink from the spring she found there. This made her dishevelled and some of her supporters were dismayed, but this act revealed the stream that soon became a focal point for pilgrimages. Although it was muddy at first, the stream became increasingly clean. As word spread, this water was given to medical patients of all kinds, and many reports of miraculous cures followed. Seven of these cures were confirmed as lacking any medical explanations by Professor Verges in 1860. The first person with a "certified miracle" was a woman whose right hand had been deformed as a consequence of an accident. Several miracles turned out to be short-term improvement or even hoaxes, and Church and government officials became increasingly concerned.The government fenced off the Grotto and issued stiff penalties for anybody trying to get near the off-limits area. In the process, Lourdes became a national issue in France, resulting in the intervention of Emperor Napoleon III with an order to reopen the grotto on 4 October 1858. The Church had decided to stay away from the controversy altogether.
Soubirous, knowing the local area well, managed to visit the barricaded grotto under cover of darkness. There, on 25 March, she said she was told: "I am the Immaculate Conception" ("que soy era immaculada concepciou"). On Easter Sunday, 7 April, her examining doctor stated that Soubirous, in ecstasy, was observed to have held her hands over a lit candle without sustaining harm. On 16 July, Soubirous went for the last time to the Grotto. "I have never seen her so beautiful before," she reported.
A garden image of the Lourdes apparition in Castlewellan, Northern IrelandMain article: Lourdes apparitions
The Church, faced with nationwide questions, decided to institute an investigative commission on 17 November 1858. On 18 January 1860, the local bishop finally declared that: "The Virgin Mary did appear indeed to Bernadette Soubirous." These events established the Marian veneration in Lourdes, which together with Fátima, is one of the most frequented Marian shrines in the world, and to which between 4 and 6 million pilgrims travel annually.
In 1863, Joseph-Hugues Fabisch was charged to create a statue of the Virgin according to Soubirous's description. The work was placed in the grotto and solemnly dedicated on 4 April 1864 in presence of 20,000 pilgrims.
Soubirous was later canonized as a saint in 1933.
The veracity of the apparitions of Lourdes is not an article of faith for Catholics. Nevertheless, all recent Popes visited the Marian shrine at some time. Benedict XV, Pius XI, and John XXIII went there as bishops, Pius XII as papal delegate. He also issued an encyclical, Le pèlerinage de Lourdes, on the one-hundredth anniversary of the apparitions in 1958. John Paul II visited Lourdes three times during his pontificate, and twice before as a bishop. As Quoted online In Wikipedia's Website.