Today we celebrate the dedication of the Basilica of Saint Mary Major, where we venerate the icon the Salus Populi Romani (Protectress of the Roman People). “Invoke the Mother of God, dear young people, to feel the sweetness of her love. Pray to her in times of trials and suffering, dear sick people. Look up to her, dear newlyweds, as the model of conjugal devotion and loyalty.”
The Church celebrates the feast of the dedication of Saint Mary Major, one of the four papal basilicas of Rome, on August 5th.
According to tradition, the Virgin Mary appeared in a vision to a faithful Christian couple, the Roman patrician John and his wife, as well as to Pope Liberius (352-366), asking them to build a church in her honour on the site where snow would fall. On August 5, 352, Esquiline Hill was covered with snow. Pope Liberius traced the shape of the church in the snow and the first basilica was built on this site. It was completed a century later by Pope Sixtus III after the Council of Ephesus in which Mary was declared Theotokos (Mother of God).
More information of Our Lady of the Snows can be found here: http://www.catholictradition.org/Mary/snows.htm