The XVI century represents a very meaningful moment for the Rho history, characterized from political ferments, manifestations of religious faith, misery, superstition, plague. In the climate of pietism replaced splendour of the Roman Apostolic Church, a report fact, is placed connected with the, construction, in 1522, of the little chapel dedicated to the Virgine della Neve, as thanks for a received grace. But the miracle that provoked the greatest fuss in all the Diocese of Milan happened the 24th April 1583, day dedicated to San Giorgio. The popular tradition and the report of the event conserved near the archives of the Milan, Court  tell the vicissitude as follows: '… It was on Sunday and some faithfuls were usual to assemble themselves in the little church for the Office of the Vergine Benedetta…' finished the function, before going to sing the vesper in Parochial Church, a certain Girolamo de Ferri went with three friends to the Oratory again, doing some oration. After some prayers, the three men went away and only Ferry remained there; while he was praying, observed that the face of the sacred image was pale more of usual, he thought that a painter had recently remaked it and he and went out without thinking about anymore. While he was returning to the country he met his friend Alessandro de Ghioldi, said Marchettino who was going to the little church, from whom he was invited to return together to the Oratory of the Virgin. While both were knelt down to pray, Ghioldi, addressing to Gerolamo said: -Look at that eye! It’s dirty, it was not like that when we have said the vesper-. Gerolamo answered: -it was like that just before when I was praying-. Ghioldi went to  a certain Maffeo to take the key,  in order to open the gate that closed the little chapel and to remove the spot from the face of the Virgin. The caretaker was not in the house, it was the mother, Caterina Candiani named the Beech-Marten, to deliver the key and also her wanted to go to the oratory. Gerolamo Ferri got on the altar, he was given a diaper and tried to clean up the face of the Virgin. He noticed that the eye of the Virgin was all reddish and that two tears of blood dropped down on the lips and a  third  one followed them stopping itself under the chin. The Parish Priest Traiano Spandrio was perceived of the fact, who wento to the place with the priest Viviani Prati and Giovanni Giolti, Apostolic Notary.Viviani got on the altar and touched the eye of the Vergin, still humid of blood, much to wet his finger. The walls had humidity traces, but the examined diaper brought obviously spots of blood. The Parish Priest perceived immediately the Ordinary of Milan.The Archbishop made to carry out surveyings with extreme rigor, and during such period other squanderers took place themselves, and testimonies were collected on extraordinary thanks that also in the past the Virgin had lavished. Saint Carl, as soon as he had the relationship, promoted further surveyings; but at the end he exclaimed: -there is the finger of God Here!-. 

4th June 1583 the Archbishop is again on  pastoral visit in Rho. Of forehead to the evidence of the facts and to the demands of the population he called the architect Pellegrino Tibaldi from Urbino ordering him to plan the construction of the church on the place of the miracle. 6 March 1584 Saint Carlo Borromeo came to Rho to put down the first stone of the huge temple dedicated to the Lady of Sorrows. In the October, Saint Carlo  was in Castellazzo, hosted by the noble family Simonetta,  to decree the foundation of the Sanctuary and supplies to the spiritual attendance of the same one. The Half of the charity must  be emploied for the construction and half for the subsistence of the clergymen, reserving to himself and his successory deciding of the material and spiritual government of the same church. Saint Carlo entrusted constructing the Sanctuary to the congregation of the Oblati. On Saint Carlo’s death,  in 1584, the Archbishop Caspar Visconti cured that the construction of the temple  had to be continued and confirmed, with Decree 24th January 1589, the administration of all the charity  and yields to the general Parish Priest of the Oblati.As a result of that there was a controversy between the Oblati Fathers and the Parish of Rho, resolved by the  Pope Gregorio XIV. In 1694 the foundations of the peristyle or porch, made of  70 columns, than, according to the design of the Pilgrim, they must  form a crown the greater order of the facade of the Sanctuary.

In 1714, with the approval of the Cardinal Archbishop Benedict Erba Odescalchi Prefect of the Sanctuary, , the clergyman Gregorio M. Martinelli,inventer of a special community of Oblati Clergymen came to Rho.

The 4th April 1721 was canonically erected the College of the Oblati Missionaries of Rho, with own rights and duties. It was decided to be built beside the Sanctuary,itself, the jobs of the peristyle were interrupted, with the forecast to restructure  the design of the façade consequently. In 1752, on initiative of the Prefect of the Sanctuary and  Senior of the College, Father De Rocchi, the architect Giuseppe Merlo was invited to restudy the design of the Dome of the Pilgrims, whose realization was considered too much expensive. Merlo decided to replace the four columns of the plan with four arches resting on eight pillars, reducing  the exteriors of the cupola and the skylight ornament .The jobs continued until the funds exhaustion, and were resumed later by  the architect Galliori who, in short time, carried out the work of the cupola, which has a diameter of 18 m. and a height, from the pavement, of m. 54. At the same time the architect Pollak traced a design for the facade in pure classic style. In the 1876  the building of the majestic college was begun and was completed in 1911. In 1888 with the installation of a second concert of bells on the high bell tower (m. 75) the work was completed and the Sanctuary assumed the current aspect. The temple has got a single nave, it is 74 meters long and it brings a decoration inspired to the pains and the glories of the Virgin. On the 4th Sunday of September,in 1895, the Sanctuary was inaugurated by the Cardinal Ferrari, the Archbishop of Milan. 3rd  February 1923 the Pope Pio XI elevated the Sanctuary to the degree of smaller basilica, adding to it all the privileges.