The Arch of Augustus was erected in 25 BC on the occasion of the Roman victory over the Salassi and was the work of Aulus Terentius Varro Murena.
Constructed from conglomerate, the arch has a single vault, with a height to the keystone of 11.4 metres. Its span is a barrel vault, constituting an extension in width of a round arch. In the monument, various styles can be recognised: The ten engaged columns which decorate its facade and its sides culminate in Corinthian capitals, while the entablature, adorned with metopes and triglyphs, is of the Doric order.
During the twelfth century, the arch contained the home of a local noble family and in 1318 a small fortification was built inside it, designed for a corps of crossbowmen. In 1716, because of the numerous leaks that were compromising the integrity of the monument, the attic that previously crowned the arch was replaced with a slate roof.
The arch's modern appearance is the result of a final intervention for restoration and consolidation which occurred in 1912 under the direction of Ernesto Schiaparelli.
The wooden crucifix displayed below the vault is a copy of the one which was placed there in 1449 as a votive offering against the flooding of the river Buthier, which flows a little to the east. The original crucifix is now housed in the Museum of Aosta Cathedral's Treasures.References:
The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.