Vaison-la-Romaine has ancient origins, as revealed by its name. Actually, up to the XIX century, not much was known about the Gallic-Roman town lying under the modern settlement and on the previous Celtic-Ligurian ones. Since the beginning of the XX century, 15 hectares of the city of Vasio Vocontiorum have been unearthed in two distinct archaeological sites: La Villasse and Puymin. The findings are on show in the Archaeological Museum Théo Desplans. The Gallic-Roman town was much wider and more populated than the present one, with about 10,000 inhabitants against the 6,500 of the present days, and it was rich in monumental public buildings, such as the theatre, the spas, bridges and aqueducts. On the right bank of the Ouvèze, there is the Romanesque cathedral of Notre-Dame de Nazareth (XI-XII cent.), built on pre-existing early Christian structures. It has a basilica plan and it was built using abundant used material from the Gallic-Roman city. Annexed to the church is the beautiful cloister of the canonicals of the cathedral. In medieval times (XIII cent.), the population settled at the foot of the castle of the counts of Toulouse, in the Haute-Ville, which then became a possession of the popes. It is only in the XVI century that the settlement is expanding again in the plane.