Seine
The port of Paris is the most important fluvial port in France: About 20.2 million tons of merchanise are handled each year, 20 miilon  tons of this merchandise come from fluvial transport.  There is a project called Seine–Nord Europe Canal, to build a high-capacity canal to connect the Paris region to the Ports of Antwerp, Dunkerque and Rotterdam, for large ships of  width and  length.