It is age-old just like all of Città Alta. The primitive structure was erected between the 5th and 6th century.
It was initially dedicated to Saint Vincent. Some pictorial and sculptural evidence of this is conserved in the Diocesan Museum. The excavations which revealed the church’s foundations brought to the light two adjacent Roman domus, highlighting the fact that the area was lived in back in Roman times. In 1689, the church was definitively consecrated to Saint Alexander, patron saint of the city. The Duomo is famous for its wealth of decor but also for its “treasure” of chalices, monstrances, altar fronts and very precious shrines. One of these is the tiara of Pope John the 23rd. The precious papal headpiece was realized in 1958 by sculptor Attilio Nani. The materials used show the absolute prestige of the composition: gold, pearls, rubies, diamonds, emeralds on silver mesh.
