[2] Returning to Italy after a long journey to Santiago de Compostela, he decided to undertake a new pilgrimage to Jerusalem and to prepare himself spiritually he took refuge at Mount Serico, in Atella, where he is the protagonist of the healing of a blind man.

At the same time it was also decided to build a church, consecrated in 1126, dedicated to the Madonna, but, contrary to what is often told, no apparitions occurred:[2] William only followed his deep devotion to the Virgin Mary.

[1] Between 1378 and 1588 the sanctuary of Montevergine experienced a profound crisis both from a spiritual and economic point of view, accentuated by a commendation of 1430, which assigned the offerings made for the abbey to men without any Christian interest.

From 1588 until the beginning of the 19th century, monastic life was fairly peaceful, although in 1611 the guesthouse was seriously damaged by a fire and in 1629 the central nave of the church collapsed;[2] from 1807, the year in which the body of William of Montevergine was moved from the abbey of Goleto to Sant'Angelo dei Lombardi in Montevergine, to 1861 a new period of crisis seriously endangered the life of the congregation itself: on 28 May 1868 the council of state decreed that the abbeys should not be subject to any type of economic suppression and therefore all the assets confiscated in the previous years were returned again;[2] in the same year the sanctuary was declared a national monument,[6] while in 1884 the meteorological station of Montevergine was inaugurated[7] At the beginning of the twentieth century the situation improved considerably and the sanctuary enjoyed the ancient fame, becoming one of the most visited in Southern Italy; During the Second World War, precisely from 1939 to 1946, it secretly hosted the Shroud of Turin,[8] not only to protect it from the bombings but also to hide it in the event that Adolf Hitler would want to take possession of it.

Also in the 1960s, the crypt, which contains the remains of San Guglielmo, the Ex-voto room and a museum, were reorganized according to modern standards only in 2000, which collects the numerous archaeological finds or jewels and works of art brought by pilgrims, dates back.

[12] The facade, divided into three compartments where the same number of entrances open, is covered in white stone and in the center there is a rose window decorated with polychrome glass depicting the coronation of the Virgin.

The entrance to the church starts with a large corner staircase which leads directly into the courtyard of the monastery and is surmounted by an iron portal, the work of the De Lamorte foundry of Naples,[21] realized in 1885, in Gothic style: past the entrance one enters a covered atrium, and then enters directly into the templeThe church has a single nave, paved in marble and is delimited on each side by three large arches, a sign of the past side aisles, now closed; in the ancient basilica there are six marble plaques which respectively recall the history of the sanctuary, thanks to Leo XIII, the visits of Umberto I, the pilgrimage of Vittorio Emanuele III on 28 August 1936, the restoration of the diocese of Montevergine and to Francesco I.

Behind the altar is the walnut wood choir, created by Benvenuto Tortelli in 1573 and characterized by small columns, putti inlaid on the armrests and the Angel with the aspergillum under the central kneeler;[23] The church is closed by an organ by Vincenzo Benvenuti built in 1896.

[24] On the right side there is a chapel dedicated to the Blessed Sacrament, inside which there is a canopy dating back to the 13th century, in Romanesque style, with Cosmatesque inlays, a gift from Mary of Hungary or her son Charles Martel: four marble lions support the four columns decorated with an alternation of white and red which symbolically depict the four tributaries of the Danube; on the architrave, in addition to two statues holding the thurible and the aspergillum, eight other small columns support the dome.

[28] On the external square there is the chapel of the Torrione, so called because it is similar to a tower, whose façade was built towards the end of the 19th century based on a design by the architect Carmine Biancardi: it is accessed via a staircase, which if done on ones knees, allows to obtain a partial indulgence; inside is a half-bust of the Redeemer dating back to 1899.

[31] The constant flow of pilgrims over the years led to benefits trickling down to local communities, so much so that numerous hostels were built in the area: today this place takes the name of Ospedaletto d'Alpinolo, deriving precisely from the high number of reception centers.

[34] Every year, on the occasion of 12 September (Most Holy Name of the Blessed Virgin Mary) and 2 February (Candlemas),[35] gays, lesbians and trans people pay homage to Mamma Schiavona with a pilgrimage to the sanctuary, called juta dei femminielli,[34][36] to then participate, together with the other pilgrims, in the dances, above all tammorriate [it],[34] taking place in the square in front.