<Tr> <Th> Basin size </Th> <Td> 12,800 km (4,900 sq mi) </Td> </Tr> <P> The Marne is a river in France, an eastern tributary of the Seine in the area east and southeast of Paris . It is 514 kilometres (319 mi) long . The river gave its name to the départements of Haute - Marne, Marne, Seine - et - Marne, and Val - de-Marne . </P> <P> The Marne starts in the Langres plateau, runs generally north then bends west between Saint - Dizier and Châlons - en - Champagne, joining the Seine at Charenton just upstream from Paris . Its main tributaries are the Rognon, the Blaise, the Saulx, the Ourcq, the Petit Morin and the Grand Morin . </P> <P> In the Champagne région, part of the flow is diverted through the artificial lake Lac du Der - Chantecoq . This ensures both flood prevention and the maintenance of minimum river flows in periods of drought . </P>

Where is the marne river on a map
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