Sant'Orso had originally a single hall, delimited by a semicircular apse. It was entirely rebuilt during the 9th century, during the Carolingian age. Later, bishop Anselm of Aosta further renovated the church, introducing a basilica plan with three naves with wooden trusses. These were replaced by Gothic cross vaults in the 15th century.
The church has a nave and two aisles divided by quadrangular pillars.
The vault was rebuilt in the 15th century. Fragments of a Romanesque series of paintings are preserved in good condition in the space between the current vault and the original ceiling. These portray scenes from the New Testament as well as a martyrdom. Stylistically they resemble the bright colours and strongly marked outlines of some of the frescoes at the Galliano Basilica near Cantù. In the right aisles is a chapel houseing the altar of St. Sebastian, also with frescoes (15th century).
The cloister has historiated capitals depicting the life of Ursus. 37 of the 42 original capital remains: they were originally in white marble, though now they mostly appear in dark gray color aftery they were washed with ash paint.
The quadrangular-plan bell tower, dating to 989, has kept some the lower 15 metres of the original medieval structure. The present structure, in Romanesque style, dates to the 12th century, and has a total height of 44 metres.
The church is home to numerous missals and reliquaries, including the relics of Ursus, which rest in the crypt. It also holds the relics of Saint Gratus of Aosta.
References:The Temple of Edfu is one of the best preserved ancient shrines in Egypt. It was built in the Ptolemaic Kingdom between 237 and 57 BC.
Edfu was one of several temples built during the Ptolemaic Kingdom, including the Dendera Temple complex, Esna, the Temple of Kom Ombo, and Philae. Its size reflects the relative prosperity of the time. The present temple initially consisted of a pillared hall, two transverse halls, and a barque sanctuary surrounded by chapels. The building was started during the reign of Ptolemy III Euergetes and completed in 57 BC under Ptolemy XII Auletes. It was built on the site of an earlier, smaller temple also dedicated to Horus, although the previous structure was oriented east–west rather than north–south as in the present site.