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 the city each year their cargo of cereals, coal, and building materials. Factories were constructed and products as diverse as sugar and boots were produced. During the Paris Commune bloodshed was so bad that the Seine ran red with blood. Traffic on the Seine entered into consciousness in a different way too—the Pre-Impressionist and impressionist painters would paint the River scenes from the Pont Neuf, to Argenteuil. And so we are left with colourful and sometimes cubist, copies of age old scenes. In 1867, the year of an exposition, another famed Paris institution came into being—that of the Bateau Mouche.