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
Sundays River South/Southeasterly direction, passing the town Graaff-Reinet in the Karoo before winding its way through the Zuurberg Mountains and then past Kirkwood and Addo in the fertile Sundays River Valley. It empties into the Indian Ocean at Algoa Bay after running through the village of Colchester, 40 km east of the city of Port Elizabeth. The Fish River-Sundays River Canal Scheme consists of a canal and tunnel system which supplies water from the Orange River to the Great Fish River Valley and subsequently to the Sundays River Valley in order to supplement the existing water supply of the Eastern Cape. Since