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
Seine River Steamers early vessels meant that positive traction by pulling on a chain against a deadman or anchor was much more effective. In the 1830s river travel was considered dangerous, so much so that insurers would put a 25 percent premium on cargoes and vessels travelling the route. The Seine is divided into three sections, the lower or Oise section, middle or Paris Section, and upper or Marne section. Ships enter the river at Le Havre through a bad tidal bore. (Victor Hugo's favourite daughter was killed while travelling in a small boat across the bore.) Oceangoing ships can travel to Rouen,