The Canal de Marans à la Rochelle, also called Canal de Marans, Canal de Rompsay or Canal de La Rochelle depending on the location, is a French canal in the Charente-Maritime department connecting the city of La Rochelle with the town of Marans. It also connects the river of the Sèvre Niortaise to the harbour at La Rochelle. The canal goes through the communes of Dompierre-sur-Mer, Andilly and Sainte-Soulle. It is 24.6 km long, with 4 locks, and has a total denivellation of 1.7 m.