Porto-Vecchio is a commune in the French department of Corse-du-Sud, on the island of Corsica. Porto-Vecchio is a medium-sized port city pl…Porto-Vecchio is a commune in the French department of Corse-du-Sud, on the island of Corsica. Porto-Vecchio is a medium-sized port city placed on a good harbor, the southernmost of the marshy and alluvial east side of Corsica. It is the seat of two cantons: Bavella and Grand Sud.