The Comtadine plain is separated from the Rhône valley by a line of hills corresponding to ancient terraces of the Rhône. It extends on the once marshy delta of the plain of the Sorgue where the Durance, Ouvèze, Coulon, Nesque, and tributaries of the adret of Mont Ventoux came together. This vast swamp was drained in the Gallo-Roman period and the Middle Ages and then irrigated in particular by the Carpentras canal built in the 19th century to divert the waters of the Durance and surround the Comtadine plain to the east. Its silty and rich soils are conducive to intensive market gardening and orchards.