VASIO(Οὐασιών: Eth. Vasiensis), a town of the Vocontii in Gallia Narbonensis, and the only town which Ptolemy (Ptol. 2.10.17) assigns to them, Vasio is mentioned by Mela (2.5) as one of the richest towns of the Narbonensis; and Pliny (Plin. Nat. 3.4) names Vasio and Lucus Augusti as the two chief towns of the Vocontii. The ethnic name Vasiensis appears in the Notitia of the Gallic Provinces (Civitas Vasiensium), and in inscriptions. The place is Vaisonin the department of Vaucluse, on the Ouvèze, a branch of the Rhone. It is now a small, decayed place; but there are remains which show that it may have been what Mela describes it to have been. The ancient remains are spread over a considerable surface. There is a Roman bridge of a single arch over the Ouvèze, which still forms the only communication between the town and the faubourg. The bridge is built on two rocks at that part of the river where the mountains which shut in the bed of the river approach nearest. There are also the remains of a theatre; the semicircle of the cavea is clearly traced, and the line of the proscenium is indicated by some stones which rise above the earth. There are also the remains of a quay on the banks of the river which was destroyed by an inundation in 1616. The quay was pierced at considerable intervals by sewers which carried to the river the water and filth of the town: these sewers are large enough for a man to stand in upright. There are also traces of the aqueducts which brought to the town the waters of the great spring of Groseau. (Breton, Mém. dei> la Société Royale des Antiquaires de France, torn. xvi., quoted by Richard et Hocquart, Guide du Voyageur. )
[G.L]