The Battle of the Trebia took place south of the Trebbia's confluence with the Seine river.
 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 [110 mi])
== Course ==The Seine can artificially be divided into five parts:the Petite Seine, "Small Seine" from the sources to Montereau-Fault-Yonnethe Haute Seine, "Upper Seine" from Montereau-Fault-Yonne to Paristhe Traverse de Paris, "the Paris waterway"the Basse Seine, "Lower Seine" from Paris to Rouenthe Seine maritime, "Maritime Seine" from Rouen to the English channel

