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 5th Parachute Brigade in taking the town. On 26 August the men of the parachute brigade, some mounted on the Cromwell tanks of the 6th Airborne Armoured Reconnaissance Regiment, raced towards the bridge from the east while the Dutch headed there from the west. The Dutch brigade arrived first, just minutes after the Germans destroyed the bridge, slightly ahead of the 7th Parachute Battalion. The Dutch brigade moved to secure the heights overlooking the river, while the 5th Parachute Brigade occupied the town. Having reached the River Seine, the division was ordered to hold firm between Honfleur and Pont Audemer