Aosta is a city of 35,000 people, capital, main centre and unique province of the region Aosta Valley. This is a town of great historic interest for its monuments and could be considered an open-air museum of Roman remains, unusual in the region. It is situated exactly in the middle of the region, in the plan where the river Dora Baltea flows. Over the town Mounts Becca and Emilius dominate the valley. The river Buthier crosses Aosta from the North to the South and is one of the main affluents of the river Dora. The so called Megalith Area of Saint Martin de Corielans, an archaeological site of the Stone Age, will become one of the most important tourist place in Aosta since 2013, when it will open to the public. The Arch of Augustus was built by the emperor after the foundation of the city in 25 b.C. and represents the Roman domination with the Porta Praetoria, the East entrance gate of the old Roman city, the theatre and the amphitheatre.
The towers represent the domains on the area during several ages, from the Romans to the family Savoy; whilst the entrance gates were four: the one mentioned was the only to resist to weather and centuries, especially because the other three towers were destroyed to built new bulidings around there.
The Roman bridge over the Buthier is pedestrian and is situated very near the Arch of Augustus; the Roman villa was discovered only 40 years ago and was built in the high-republican period; the necropolis is outside the old wall. The Cathedral has a medieval origin and is considered as a typical example of holy art of the city. The structure is hard to define as it was begun in the 12th century and ended only in the middle of the 19th century. The Collegiata di Sant’Orso conserves some works of a unique beauty as for example the medieval mosaic and cloister and the crypt of the Saint. The Chapel of the Saint Cross and the Cross of Calvino are modern buildings, while the most recent is anyway Piazza Chanoux, the main square dedicated to the Aosta Valley hero, tortured and killed by the fascists in 1944.