The collegiate church of Santi Pietro e Orso is, with the cathedral, the greatest testimony of sacred art in the Aosta Valley. Excavations have shown that the area was occupied by a large necropolis outside the town. The original church, a single hall, was rebuilt and enlarged in the ninth century, in the Carolingian age; in 989 it was given a bell tower, whose remains can still be seen incorporated in the façade. Bishop Anselm I then had it remodelled in Romanesque forms, with a nave and two aisles: from that period remain the walls, the piers, the crypt and the frescoes. At the end of the fifteenth century the prior Giorgio di Challant gave it its late Gothic appearance: the façade was remade between 1492 and 1494, and the trussed roof was replaced by cross vaults.
What to see
Over the little square of Sant'Orso rises the Romanesque bell tower, forty-four metres high, standing apart from the church: it was erected in the twelfth century as part of a defensive system and served as a refuge in case of danger. The lower part is made of enormous squared blocks; higher up open three-light windows and a four-light one. Inside are twelve bells: the largest, cast in France in 1589, is the biggest in the Aosta Valley. The façade has a pointed portal under a tall gable with a brick frame.
Inside, a Baroque screen of polychrome marbles separates the nave from the choir. Below floor level you can see a twelfth-century mosaic of black and white tesserae, brought to light by the excavations of 1999. In the choir are the wooden stalls carved around 1487, and in the apse five stained-glass windows painted between the fifteenth and sixteenth centuries. From the end of the side aisles a stair goes down to the crypt, the oldest part. The Romanesque cloister, built in the years just after 1133, keeps thirty-seven of the fifty-two original marble capitals.
Visiting
Opening times of church and cloister should be checked before going. The Treasury, in the sacristy, is reported as open only on specific occasions; the priory beside the church, with its octagonal tower, cannot be visited.
Our editors' tip
The capitals of the cloister are dark, but they are of white marble. To waterproof them they were given a coat of a transparent gluey compound mixed with ash, which over time oxidised and darkened them for good.
