The Canal du Midi passes just north of Carcassonne's historic centre, linking the Atlantic at Toulouse to the Mediterranean at Sète across 240 kilometres of southern France. The stretch around Carcassonne is one of the most beautiful: the canal runs through a tunnel of ancient plane trees, with stone bridges, lock-keepers' houses, and the occasional working barge moving through the green corridor.
The Pont Marengo bridge connects the Bastide Saint-Louis to the railway station across the canal. You can walk or cycle the towpath in both directions — east toward the Fresquel Aqueduct and the vine-growing country beyond, or west toward the suburbs of Carcassonne. Boat rentals are available and a canal boat trip, even just for a few hours, gives a completely different view of the landscape. The Canal du Midi is a UNESCO World Heritage Site in its own right.