The Franciscans built a church in 1881 at Cana, a Galilean town five miles northwest of Nazareth, between Sepphoris and Tiberias, in the small village now known as Kefr Kanna. This shrine commemorates Mary's mediation in the miracle of Cana. Many improvements were made to the building for the jubilee year 2000.
The miracle of the wedding at Cana is recounted in the Gospel of John, Chapter 2. We suggest that you read this page of the gospel.
Mary is not called "Mary" but "the mother of Jesus"; then Jesus calls her "Woman" (just as he did on the Cross); and then once again, John calls her "the mother of Jesus." Mary's mediation is a maternal mediation.
Her mediation consists in speaking to Jesus on behalf of others: "They have no wine." Then she tells the servants in the name of Jesus: "Do whatever he tells you."
Jesus asks the servants to fill 6 jars with water, then he changes the water into wine. This sign has deep symbolic value. Notably, the wine also symbolizes the Torah revealed by the Messiah. We invite you to read the other articles on biblical commentaries.
Jesus returned to Cana to do another miracle, the healing of the servant of a Roman centurion (Jn 4: 46-54), so that these two signs given in Cana would announce the formation of a new nation of believers, a people descended from Judaism with the disciples at Cana, and from the pagans with the centurion who also became a believer.