The Canal du Midi is a Unesco World Heritage Site. Started in 1667, and completed fourteen years later, it was conceived, built and partly financed by Pierre-Paul Riquet, from Béziers. It opened in 1681, the year after Riquet's death. The canal runs from Sète to Toulouse where it meets the Canal Latéral which runs to the Garonne river and to Bordeaux. From Sète the Canal du Rhône links the Canal du Midi to the Rhône River, and the Canal de la Robine joins Narbonne to the Canal du Midi between Béziers and Carcassonne.

The purpose of the Canal was to enable direct transport between the Atlantic and Mediterranean without having to go round the Iberian peninsular. The Canal du Midi traverses a land rise of 190 metres between the two coasts, through a series of 65 locks, and was the engineering feat of its day. The Fonseranes locks at Béziers are in themselves an extraordinary accomplishment; a series of eight locks back-to-back, 300 metres in length and traversing a vertical height of 21.5 metres.

As part of the development of the canal a new port was built on the Mediterranean Sea. Construction of the port of Sète started in the 1670s and the town was soon to become one of the largest and richest in the region.

More than one hundred bridges were built across the canal and 45,000 trees were planted along its banks to maintain the banks and provide shade. The canal was a commercial success, but it took nearly one hundred years for the Riquet family to pay off the debts of Pierre-Paul Riquet. Today Pierre-Paul Riquet is honoured in Béziers with a statue in the centre of the main avenue, the appropriately-named Allées Paul Riquet.

From engineering wonder to commercial transportation success, the Canal now has become a centre for tourism. The beauty of the canal, and the land through which it passes, attracts many people to take boating trips or hire canal barges for holidays. More, still, discover the canal by car and stop at many of the restaurants along its route. The practical planting of 45,000 trees endows the latter-day canal with a sense of peace, beauty and permanence that makes it unique.

The Canal du Midi passes through some interesting areas. The Étang de Thau, with its oyster beds; Sète, the original canal port with its fishing boats and jousting tournaments; Béziers, centre of the region's wine trade and rugby, famous for the Cathar massacre of 1209; the historic site of the Oppidum at Ensérune, dating back to 600BC and the nearby drained lake, the Étang du Montady; Carcassonne with the largest mediaeval castle in Europe and many small towns and villages with historic churches and cathedrals.