Seine Commercial craft (barges and push-tows) can use the river from Marcilly-sur-Seine, to its mouth. At Paris, there are 37 bridges. The river is only above sea level from its mouth, making it slow flowing and thus easily navigable. The Seine Maritime, from the English Channel at Le Havre to Rouen, is the only portion of the Seine used by ocean-going craft. The tidal section of the Seine Maritime is followed by a canalized section ("Basse Seine") with four large multiple locks until the mouth of the Oise at Conflans-Sainte-Honorine (170 km). Smaller locks at Bougival and at Suresnes lift the
6th Airborne Division advance to the River Seine withdraw. Fighting several small battles, by the end of the month they reached their objective at the River Seine. Here the division halted until early in September, when they returned to England to prepare for further airborne operations later in the war. On 6 June 1944, the 6th Airborne Division landed in Normandy. Their mission was to secure the left flank of the invasion zone, by occupying and dominating the high ground between the River Orne and the River Dives. Despite the parachute troops being widely scattered, they managed to complete all of their objectives. After six days of counter-attacks