In 1291, when the crusaders left the Holy Land for good and the Muslim armies, as they advanced, sacked all the sacred Christian edifices, the walls of the house of the Blessed Virgin in Nazareth were transported first to Dalmatia (today's Albania and Croatia), then, on the night of December 9-10, 1294, to the ancient territory of Recanati (near Ancona, Italy), first close to the harbor and then to the hill where the house of Mary still stands today (Loreto).
According to a popular tradition never challenged by the long series of popes who have shown their attachment to the Holy House of Loreto, it was through the ministry of angels that God preserved the Holy House and transported it - although some recent studies suggest that it might have happened through human means.
The Basilica of Nazareth and the Basilica of Loreto are like Siamese twins, for each contains a part of the House of Mary, two parts which, according to tradition, were separated from each other. This is confirmed by the results of archaeological excavations carried out in Nazareth, in the Church of the Annunciation, between 1955 and 1960, and in Loreto in the basement of the Holy House between 1962 and 1965.
In Nazareth, the excavations showed that the house of the Virgin, like the other houses in the neighborhood, consisted of a cave cut into the rock, which served as an annex, and a three-walled room standing in the extension of the cave. If the two parts were reunited, they would perfectly fit together. The excavations also confirmed that the Holy House of Loreto was built in the same place as the grotto, and that Mary’s house was venerated as early as the first century.
The Holy House of Loreto was known early on for having no foundation. It has many other anomalies: for example, part of its walls are made of stone, which is not a building material in these parts because of the absence of quarries; its only door faces north, thus exposed to all the elements; its only window faces west, thus receiving only limited light, etc. But, what is absurd in the region of Loreto makes absolute sense in the region of Nazareth!