This is probably the oldest Marian sanctuary; its origin traditionally dates back to Saint Eusebius, Bishop of Vercelli at the end of the 4th century. The first certain documents relating to the sanctuary date back, however, to the 13th century, when, next to the sacellum, the primitive votive chapel, created to host an ancient effigy of Mary, a larger church was built, which was then united to the chapter of Santo Stefano of Biella in 1459. The town of Biella then vowed that the church should be rebuilt from 1599 onwards, incorporating Eusebius’ votive chapel which would form the nucleus of the current sanctuary; in 1620 the entrance path was completed and in 1640 the courtyards began to be built, which were then completed in the 18th and 19th centuries. Some of the major architects from Piemonte worked towards completing the church: the second square is characterised by buildings erected between 1740 and 1750 and designed by Francesco Gallo; the majestic staircase with three flights of stairs is by Pietro Giuseppe Beltramo on a design by Filippo Juvarra; the so-called Piazzale Sacro (‘holy square’) is by Pietro Arduzzi and can be accessed through a double arcade with twin columns, and at its centre there is the Porta Regia (‘royal door’) erected on the wish of Cardinal Maurizio (son of Carlo Emanuele I), and completed by Juvarra. On the side of the complex, the Basilica, dating back to the years 1600-1624, and largely by Carlo di Castellamonte, hosts several noteworthy works of art, including the goblet and the pastoral which belonged, according to the tradition, to Saint Eusebius and which were donated by king Vittorio Emanuele I. The Museo dei Tesori holds, in its four rooms, the gold, jewels, the religious paraments and the documents which, throghout the centuries, have narrated the history of the sanctuary, including a ‘Sacra Famiglia’ (‘Holy Family’) by Gaudenzio Ferrari.
